27E: The Sardis Iron
Georgia’s Largest Meteorite
By
Thomas Thurman
Posted 05/Sept/2022
“A Georgia meteorite might be one of the oldest falls that has thus far been found. Reasonably good evidence indicates that the Sardis Iron fell in a former geologic period; however, this cannot be proven beyond doubt.” That’s what E. P. Henderson & A. S. Furcron said in 1966 about the Sardis Iron meteorite from Jenkins County, Georgia. (1) Two meteorite experts, in their day.
The large Sardis Iron meteorite was found and recovered from sediments identified in a 1942 paper as the Hawthorn Formation which is Middle Miocene and roughly 10 to 15 million years old. Later research would show that the sediments are at least 20 million years old. (2)
In Spring 2023 Georgia Backroads published a versiion of this story, author by myself, on page 14. I'll admit to being disappointed by the article, no mention is made of this website though the editor & I had discussed this. However the fault is mine, when the final proof was ready I was busy with work and didn't see the editor's email in my personal account until the day after the deadline. The email was a week old, so the omission is on me. I missed my opportunity to comment. Still, I'm proud of the piece.
A pdf file of that article can be downloaded below.
A pdf file of that article can be downloaded below.
Oldest Meteorite?
Let’s deal with this “oldest” issue right now. No, the Sardis Iron is not the world’s oldest known meteorite.
I contacted Ed Albin, Associate Professor of Space & Earth Sciences at American Public University and Instructor of Geology at Georgia State University. Ed knows so much more about meteorites and tektites than I. He was certainly aware of older specimens. He forwarded a link to a 2017 article by David Boehnlein in Astronomy magazine describing four limestone slabs, each containing a stony meteorite, at Chicago Field Museum of Natural History. (3) These limestone slabs date back to the Ordovician Period (443 to 485 million years ago). One is just inches from cephalopod fossil. The slabs are from the Thorsberg quarry near the town of Kinnekulle in southern Sweden.
It is important to note that the Thorsberg quarry meteorites are stones, not irons. Stony meteorites are not as susceptible to weathering as irons. The idea of meteorites hiding in limestone beds is compelling, surely there are more… Thanks Ed
The Sardis remains Georgia’s largest. It also represents a curious find with an interesting history, and though it’s been properly & thoroughly researched by experts, it still presents some difficult to answer questions.
Let’s deal with this “oldest” issue right now. No, the Sardis Iron is not the world’s oldest known meteorite.
I contacted Ed Albin, Associate Professor of Space & Earth Sciences at American Public University and Instructor of Geology at Georgia State University. Ed knows so much more about meteorites and tektites than I. He was certainly aware of older specimens. He forwarded a link to a 2017 article by David Boehnlein in Astronomy magazine describing four limestone slabs, each containing a stony meteorite, at Chicago Field Museum of Natural History. (3) These limestone slabs date back to the Ordovician Period (443 to 485 million years ago). One is just inches from cephalopod fossil. The slabs are from the Thorsberg quarry near the town of Kinnekulle in southern Sweden.
It is important to note that the Thorsberg quarry meteorites are stones, not irons. Stony meteorites are not as susceptible to weathering as irons. The idea of meteorites hiding in limestone beds is compelling, surely there are more… Thanks Ed
The Sardis remains Georgia’s largest. It also represents a curious find with an interesting history, and though it’s been properly & thoroughly researched by experts, it still presents some difficult to answer questions.
The Smithsonian is given a Taste…
“In April of 1940 a small, rusted fragment about the size of a half dollar was sent to the United States National Museum (Smithsonian) by Fred M. Allen, of the Chamber of Commerce in Waynesboro, GA. It was found to be unusually heavy. This, and certain other properties suggested that it might be a meteorite. A chemical test on the specimen disclosed the presence of nickel. Further examination showed some of the unoxidized nickel-iron alloy, these observations proved that it was part of a meteorite. Mr. Allen was promptly notified of his find and urged to furnish additional information as well as a larger and better specimen for examination.” (3) That’s how the Sardis Iron was introduced to science.
“In April of 1940 a small, rusted fragment about the size of a half dollar was sent to the United States National Museum (Smithsonian) by Fred M. Allen, of the Chamber of Commerce in Waynesboro, GA. It was found to be unusually heavy. This, and certain other properties suggested that it might be a meteorite. A chemical test on the specimen disclosed the presence of nickel. Further examination showed some of the unoxidized nickel-iron alloy, these observations proved that it was part of a meteorite. Mr. Allen was promptly notified of his find and urged to furnish additional information as well as a larger and better specimen for examination.” (3) That’s how the Sardis Iron was introduced to science.
The Nickel Test
Nickel is present in iron meteorites but typically not in terrestrial or man-made iron. Since many people are allergic to nickel and it is commonly in less expensive jewelry, nickel test kits are available at nearly all pharmacies. A nickel test is one of the quickest ways to confirm meteorite.
Chamber of Commerce Support
In May 1940 Fred Allen supplied the Smithsonian a larger sample as well as accurate estimates about the size of the main mass. Additionally, the Chamber of Commerce put the Smithsonian directly in contact with their source of information, County Sanitarian W. H. Powell. The National Museum thanked Mr. Allen for contacting them and for assisting with the meteorite.
Today it’s hard to imagine any Chamber of Commerce in Georgia assisting in a scientific endeavor. Efforts by the author of this page to involve or generate interest in earth science tourism development with the Georgia state tourism office or local chambers of commerce have fallen on deaf ears. In 1940, science was still seen as the hope for a better the future instead of a burden on the economy.
Nickel is present in iron meteorites but typically not in terrestrial or man-made iron. Since many people are allergic to nickel and it is commonly in less expensive jewelry, nickel test kits are available at nearly all pharmacies. A nickel test is one of the quickest ways to confirm meteorite.
Chamber of Commerce Support
In May 1940 Fred Allen supplied the Smithsonian a larger sample as well as accurate estimates about the size of the main mass. Additionally, the Chamber of Commerce put the Smithsonian directly in contact with their source of information, County Sanitarian W. H. Powell. The National Museum thanked Mr. Allen for contacting them and for assisting with the meteorite.
Today it’s hard to imagine any Chamber of Commerce in Georgia assisting in a scientific endeavor. Efforts by the author of this page to involve or generate interest in earth science tourism development with the Georgia state tourism office or local chambers of commerce have fallen on deaf ears. In 1940, science was still seen as the hope for a better the future instead of a burden on the economy.
The Story of Discovery Begins…
The rusty old iron was discovered in 1940 “when a farmer snagged his plow” while working a cotton field, a field which had been under continuous cultivation for 50-plus years. While the authors of these papers name many of the men involved in this history, sadly, the name of the man driving the plow is never mentioned.
The rusty old iron was discovered in 1940 “when a farmer snagged his plow” while working a cotton field, a field which had been under continuous cultivation for 50-plus years. While the authors of these papers name many of the men involved in this history, sadly, the name of the man driving the plow is never mentioned.
A Black Farmer?
The fact that the man driving the plow is unnamed is inexcusable, the name of anyone making a significant scientific discovery should be recorded. I (the author) suspect that this shows a black man discovered the Sardis, but I have no evidence. The quote in the original 1942 paper is “when a boy fouled his plow” and the term “boy” is used again in the same paragraph. Yet, still in the same paragraph the term “plowman” is used.
The fact that “boy” was once a socially acceptable term for whites to use when discussing black men is a source of ongoing shame for the South. A man is a man no matter his race.
“Though the cottonfield in which this discovery was made has been under constant cultivation for about 50 years, the meteorite was not found until 1940, when a boy fouled his plow in such a manner as to cause him to investigate the obstruction. There was either something different in the manner in which the plow snagged that day or else the boy's interests had been freshly aroused by the frequent rumors of buried treasures often reported to be in this part of the country. When General Sherman made his famous march to the sea he passed through this area, and rumor still has it that the treasures of many families were buried to protect them from the invading army and have never been relocated. The plowman knew there were no rocks in this vicinity, so that anything causing his plow to snag was rather unusual and perhaps a hidden treasure. He probably guessed that his "pot of gold" lay right here.”
Furthermore, I suspect that the landowners were black. Again, they are not identified by name but surely the researchers requested their permission to enter and excavate on their property. The same 1942 report states; “The present owner of the land has tilled this field for nearly 50 years, and, as the farm belonged to his father, he would almost certainly have heard about it if such a large meteorite had fallen on his farm within the past 75 years.”
Jenkins County Tax Assessors Office
Land Ownership
When I contacted the Jenkin’s County Tax Assessors Office in September 2022, Vicky Patrick told me that the only pertinent record was a deed from 1923, in which Fannie Brinson had sold the property to Clyde Smolowsky. The deed described property as the “Henry Bonnell Place or the Isaiah A. Bell Place.” Of course, having names tells us little about the race of the owners or purchasers.
The 1966 paper on Georgia’s meteorites never uses the term “boy” and refers to either the “plowman” or “farmer” when discussing the Sardis Iron discoverer. Social mores had changed considerably between 1942 and 1966, they're changing still. Though the farmer still isn’t named in the research, this might simply be a matter of the name missing from the 1942 record they were referencing.
The fact that the man driving the plow is unnamed is inexcusable, the name of anyone making a significant scientific discovery should be recorded. I (the author) suspect that this shows a black man discovered the Sardis, but I have no evidence. The quote in the original 1942 paper is “when a boy fouled his plow” and the term “boy” is used again in the same paragraph. Yet, still in the same paragraph the term “plowman” is used.
The fact that “boy” was once a socially acceptable term for whites to use when discussing black men is a source of ongoing shame for the South. A man is a man no matter his race.
“Though the cottonfield in which this discovery was made has been under constant cultivation for about 50 years, the meteorite was not found until 1940, when a boy fouled his plow in such a manner as to cause him to investigate the obstruction. There was either something different in the manner in which the plow snagged that day or else the boy's interests had been freshly aroused by the frequent rumors of buried treasures often reported to be in this part of the country. When General Sherman made his famous march to the sea he passed through this area, and rumor still has it that the treasures of many families were buried to protect them from the invading army and have never been relocated. The plowman knew there were no rocks in this vicinity, so that anything causing his plow to snag was rather unusual and perhaps a hidden treasure. He probably guessed that his "pot of gold" lay right here.”
Furthermore, I suspect that the landowners were black. Again, they are not identified by name but surely the researchers requested their permission to enter and excavate on their property. The same 1942 report states; “The present owner of the land has tilled this field for nearly 50 years, and, as the farm belonged to his father, he would almost certainly have heard about it if such a large meteorite had fallen on his farm within the past 75 years.”
Jenkins County Tax Assessors Office
Land Ownership
When I contacted the Jenkin’s County Tax Assessors Office in September 2022, Vicky Patrick told me that the only pertinent record was a deed from 1923, in which Fannie Brinson had sold the property to Clyde Smolowsky. The deed described property as the “Henry Bonnell Place or the Isaiah A. Bell Place.” Of course, having names tells us little about the race of the owners or purchasers.
The 1966 paper on Georgia’s meteorites never uses the term “boy” and refers to either the “plowman” or “farmer” when discussing the Sardis Iron discoverer. Social mores had changed considerably between 1942 and 1966, they're changing still. Though the farmer still isn’t named in the research, this might simply be a matter of the name missing from the 1942 record they were referencing.
Returning to the History
When he snagged his plow, he became curious. His father owned and worked this field before him, he knew there were no naturally occurring rocks. He’d never before gotten caught on a rock. Jenkins County is in east Georgia, kind of between Augusta and Savannah. Rumors of buried treasure linger in east Georgia. Sherman’s March to the Sea passed this way during the Civil War. Wealthy landowners hadn’t wanted their valuables seized by Sherman’s army and perhaps some of the buried treasures had never been recovered.
The farmer uncovered the offending object, it was just a rock. Still, just to be sure he dug around it and checked very closely, but he only found more of the typical orange-red local sandy clay. There was no chest of Confederate gold. With the help of neighbors, a deeper hole was dug and the offending rock was tipped into it so that it’d be well below the plow-blade and cause no further trouble.
In the process of relocation chips and fragments broke off the main mass, they were curiously heavy. That re-invigorated the farmer’s curiosity and so advice was sought from Mr. Powell, the County Sanitarian, as to the nature of the rock. Mr. Powell sought out Mr. Allen of the Chamber of Commerce and off a fragment went to the Smithsonian. There, the sample found E. P. Henderson and C. Wythe Cooke. Henderson was the national expert in meteorites. Cooke was one of the most accomplished geologists in the USA.
The meteorite remained buried for nearly a year until Mr. Powell returned with a wrecking truck, removed it from the field, crated it, and shipped it off to the United States National Museum in Washington, the Smithsonian.
Though not stated in the Sardis Iron literature, I would assume the Smithsonian purchased the meteorite. Returning to the 1966 text of Meteorites in Georgia, Henderson and Furcron state; “One of the chief purposes of this article is to encourage others to look for meteorites because they are important scientific specimens and to cause the public to respect the specimens, which should be given or sold to institutions where meteorites are preserved and studied.”
One hopes the unnamed plowman found some share of any potential “treasure” paid for the meteorite.
When he snagged his plow, he became curious. His father owned and worked this field before him, he knew there were no naturally occurring rocks. He’d never before gotten caught on a rock. Jenkins County is in east Georgia, kind of between Augusta and Savannah. Rumors of buried treasure linger in east Georgia. Sherman’s March to the Sea passed this way during the Civil War. Wealthy landowners hadn’t wanted their valuables seized by Sherman’s army and perhaps some of the buried treasures had never been recovered.
The farmer uncovered the offending object, it was just a rock. Still, just to be sure he dug around it and checked very closely, but he only found more of the typical orange-red local sandy clay. There was no chest of Confederate gold. With the help of neighbors, a deeper hole was dug and the offending rock was tipped into it so that it’d be well below the plow-blade and cause no further trouble.
In the process of relocation chips and fragments broke off the main mass, they were curiously heavy. That re-invigorated the farmer’s curiosity and so advice was sought from Mr. Powell, the County Sanitarian, as to the nature of the rock. Mr. Powell sought out Mr. Allen of the Chamber of Commerce and off a fragment went to the Smithsonian. There, the sample found E. P. Henderson and C. Wythe Cooke. Henderson was the national expert in meteorites. Cooke was one of the most accomplished geologists in the USA.
The meteorite remained buried for nearly a year until Mr. Powell returned with a wrecking truck, removed it from the field, crated it, and shipped it off to the United States National Museum in Washington, the Smithsonian.
Though not stated in the Sardis Iron literature, I would assume the Smithsonian purchased the meteorite. Returning to the 1966 text of Meteorites in Georgia, Henderson and Furcron state; “One of the chief purposes of this article is to encourage others to look for meteorites because they are important scientific specimens and to cause the public to respect the specimens, which should be given or sold to institutions where meteorites are preserved and studied.”
One hopes the unnamed plowman found some share of any potential “treasure” paid for the meteorite.
The Research Papers
The 1942 paper was authored by E. P. Henderson and C. Wythe Cooke (2) and published through the United States National Museum soon after the meteorite was recovered. Today that institution is called the Smithsonian National Museum of Natural History. In 1966 E. P. Henderson teamed up with A.S. Furcron and published a paper on Georgia’s meteorites where the Sardis Iron was discussed in detail again. (1) That’s where I first read of the Sardis. Sadly, the 1966 paper on Georgia’s meteorites has never been digitalized and is not available online.
When the meteorite arrived at the Smithsonian Institution it weighed 1,740 lbs and was 33” X 28” x 12” but there was clear evidence that weathering had already removed an unknown amount of material. Another problem rests in the fact that samples from the Sardis Iron decompose very quickly. Both the 1942 & 1966 papers agree that Sardis samples tarnish and weather quickly in the lab. There’s a report of one polished sample weighing about 5 pounds (2267 grams) that oxidized (rusted) into a pile of iron oxide dust in three months (1). The 1942 paper insists that weathering in the field can be very different, and they argue that if the meteorite were buried, it could be protected from weathering. This is certainly possible, but conditions would have to be perfect.
It should be stated here that the original 1942 paper states that the Sardis weighed 1,740 lbs at arrival, but the 1966 paper states the weight as 1,760 lbs. In this article we’re staying with the 1,740 lbs of the original paper.
The 1966 paper reports that chlorides were detected on a polished surface of the meteorite and this could be an artifact from exposure to sea water. But the next sentence explains that museum used tap water to cool and lubricate the band saw which cut the meteorite and this tap water could have been the chloride source.
The 1942 paper was authored by E. P. Henderson and C. Wythe Cooke (2) and published through the United States National Museum soon after the meteorite was recovered. Today that institution is called the Smithsonian National Museum of Natural History. In 1966 E. P. Henderson teamed up with A.S. Furcron and published a paper on Georgia’s meteorites where the Sardis Iron was discussed in detail again. (1) That’s where I first read of the Sardis. Sadly, the 1966 paper on Georgia’s meteorites has never been digitalized and is not available online.
When the meteorite arrived at the Smithsonian Institution it weighed 1,740 lbs and was 33” X 28” x 12” but there was clear evidence that weathering had already removed an unknown amount of material. Another problem rests in the fact that samples from the Sardis Iron decompose very quickly. Both the 1942 & 1966 papers agree that Sardis samples tarnish and weather quickly in the lab. There’s a report of one polished sample weighing about 5 pounds (2267 grams) that oxidized (rusted) into a pile of iron oxide dust in three months (1). The 1942 paper insists that weathering in the field can be very different, and they argue that if the meteorite were buried, it could be protected from weathering. This is certainly possible, but conditions would have to be perfect.
It should be stated here that the original 1942 paper states that the Sardis weighed 1,740 lbs at arrival, but the 1966 paper states the weight as 1,760 lbs. In this article we’re staying with the 1,740 lbs of the original paper.
The 1966 paper reports that chlorides were detected on a polished surface of the meteorite and this could be an artifact from exposure to sea water. But the next sentence explains that museum used tap water to cool and lubricate the band saw which cut the meteorite and this tap water could have been the chloride source.
As we’ll see in the coming text, the elevation of the meteorite’s discovery site was roughly 250 feet above sea level. There were a few periods in the last million years, when sea levels were significant higher, perhaps high enough to submerge Jenkin’s County. There were certainly periods in the last 20 million years when Jenkins County would have been submerged.
There is also evidence that the meteorite was exposed to ground water, but water tables, like sea levels, frequently shift. Glaciers haven’t reached Georgia in more than a hundred million years. Neither is there a direct path for glacial melt flood water to reach Georgia. However, glacial retreat events in the last million years would have led to epic monsoon rains in Georgia which would have greatly increased ground water tables and dramatically swollen the rivers. The evidence for vast river flood plains is common on Georgia’s Coastal Plain. The discovery site for the Sardis is about 15 miles from the Savannah River, and the terrain is fairly contoured, so it is possible that during glacial monsoon flooding the area could have been inundated by a swollen Savannah River.
The 1942 authors stated; “Evidence indicates that it is a very old fall, dating probably from middle Miocene times. It was found in a district in which craterlike depressions are abundant, but it has no apparent connection with these depressions.” The authors are referring to Carolina Bays. (See section 20D of this website) There is absolutely no evidence that Carolina Bays are impact related and there is absolutely no evidence that the Sardis Iron is in any way related to the Carolina Bays. Carolina Bays are a separate, stand-alone mystery and subject of ongoing debate.
The 1942 authors continue; “It is likewise possible that the Sardis meteorite fell into the sea in Miocene times and had its impact cushioned by striking the water, in which it gently settled to the bottom and was buried by the slowly accumulating Hawthorne formation. If this were true, corrosion would be active for a while, but the thickening oxide crust would offer increased protection as time elapsed. Furthermore, the sediments would, in all probability, soon cover it, thereby decreasing the circulation of water and retarding the rate of alteration. If the Sardis Iron was incorporated in the Miocene beds at the time of their formation, the meteorite would not have become exposed to rapidly circulating water or air until late Pleistocene time or possibly until the Recent epoch, by which time a considerable thickness of upper Miocene and Pliocene sediments had been removed, and the level of permanent saturation had fallen below the meteorite.”
They continue’ “Its arrival on the earth probably preceded that of the white man to this continent by countless centuries.”
If the Sardis Iron struck Georgia during a Miocene high stand of sea levels it would not have “gently settled” to the bottom. Even if this sea was 100 feet deep at Jenkins County this still would have been a violent impact. Likewise, it seems unlikely (to this author) that the Sardis Iron could’ve survived Georgia’s humidity for thousands of years, much less millions or tens of millions of years, even if it was buried beneath sandy soil. Again, a five pound sample turned into a pile of rust dust in just 90 days.
There is also evidence that the meteorite was exposed to ground water, but water tables, like sea levels, frequently shift. Glaciers haven’t reached Georgia in more than a hundred million years. Neither is there a direct path for glacial melt flood water to reach Georgia. However, glacial retreat events in the last million years would have led to epic monsoon rains in Georgia which would have greatly increased ground water tables and dramatically swollen the rivers. The evidence for vast river flood plains is common on Georgia’s Coastal Plain. The discovery site for the Sardis is about 15 miles from the Savannah River, and the terrain is fairly contoured, so it is possible that during glacial monsoon flooding the area could have been inundated by a swollen Savannah River.
The 1942 authors stated; “Evidence indicates that it is a very old fall, dating probably from middle Miocene times. It was found in a district in which craterlike depressions are abundant, but it has no apparent connection with these depressions.” The authors are referring to Carolina Bays. (See section 20D of this website) There is absolutely no evidence that Carolina Bays are impact related and there is absolutely no evidence that the Sardis Iron is in any way related to the Carolina Bays. Carolina Bays are a separate, stand-alone mystery and subject of ongoing debate.
The 1942 authors continue; “It is likewise possible that the Sardis meteorite fell into the sea in Miocene times and had its impact cushioned by striking the water, in which it gently settled to the bottom and was buried by the slowly accumulating Hawthorne formation. If this were true, corrosion would be active for a while, but the thickening oxide crust would offer increased protection as time elapsed. Furthermore, the sediments would, in all probability, soon cover it, thereby decreasing the circulation of water and retarding the rate of alteration. If the Sardis Iron was incorporated in the Miocene beds at the time of their formation, the meteorite would not have become exposed to rapidly circulating water or air until late Pleistocene time or possibly until the Recent epoch, by which time a considerable thickness of upper Miocene and Pliocene sediments had been removed, and the level of permanent saturation had fallen below the meteorite.”
They continue’ “Its arrival on the earth probably preceded that of the white man to this continent by countless centuries.”
If the Sardis Iron struck Georgia during a Miocene high stand of sea levels it would not have “gently settled” to the bottom. Even if this sea was 100 feet deep at Jenkins County this still would have been a violent impact. Likewise, it seems unlikely (to this author) that the Sardis Iron could’ve survived Georgia’s humidity for thousands of years, much less millions or tens of millions of years, even if it was buried beneath sandy soil. Again, a five pound sample turned into a pile of rust dust in just 90 days.
Description of the Sardis Iron, 1942
As stated above, when received by the Smithsonian in 1942 the meteorite’s dimensions were 33” by 28” by 16” and the general shape was that of a flattened ellipsoid. But the authors point out that this meant little since an unknown amount of material had been removed by weathering. No features such as flight markings or the original crust remained.
It didn’t look like a meteorite, in fact it was encrusted with enough rust-stained sand that it looked like sandstone. In color and appearance, it resembled a “mass of limonite” but closer examination revealed connecting fractures crossing the surface in a pattern resembling shrinkage cracks in sun dried mud. Many of the fractures were as much as 2” deep and researchers observed traces of octahedral structure.
It was too large and heavy to be put on the Smithsonian’s band saw, so it couldn’t be sectioned. “It would have been interesting to learn to what depth the unfractured meteorite had been altered.”
Weathered soil was removed and 20 pounds of small fragments were found. Some of these resembled brown sandstone with limonite acting as a cementing medium for the sand grains. After these pieces were cut and polished it was noted that some of the larger areas of limonite had octahedral structure. It was meteoric iron completely altered to a brown oxide, a rusted-iron dust. This brown oxide, this rust-dust, was found to have significant amounts of nickel. This was proof that the meteorite had been in-part dissolved and carried away by groundwater.
Polished surfaces reveal that the Sardis Iron belonged to the coarse octahedrite group.
The Smithsonian retains several hundred pound of the weathered Sardis Iron in their Washington DC collections, additional small samples are scattered across several museums globally.
As stated above, when received by the Smithsonian in 1942 the meteorite’s dimensions were 33” by 28” by 16” and the general shape was that of a flattened ellipsoid. But the authors point out that this meant little since an unknown amount of material had been removed by weathering. No features such as flight markings or the original crust remained.
It didn’t look like a meteorite, in fact it was encrusted with enough rust-stained sand that it looked like sandstone. In color and appearance, it resembled a “mass of limonite” but closer examination revealed connecting fractures crossing the surface in a pattern resembling shrinkage cracks in sun dried mud. Many of the fractures were as much as 2” deep and researchers observed traces of octahedral structure.
It was too large and heavy to be put on the Smithsonian’s band saw, so it couldn’t be sectioned. “It would have been interesting to learn to what depth the unfractured meteorite had been altered.”
Weathered soil was removed and 20 pounds of small fragments were found. Some of these resembled brown sandstone with limonite acting as a cementing medium for the sand grains. After these pieces were cut and polished it was noted that some of the larger areas of limonite had octahedral structure. It was meteoric iron completely altered to a brown oxide, a rusted-iron dust. This brown oxide, this rust-dust, was found to have significant amounts of nickel. This was proof that the meteorite had been in-part dissolved and carried away by groundwater.
Polished surfaces reveal that the Sardis Iron belonged to the coarse octahedrite group.
The Smithsonian retains several hundred pound of the weathered Sardis Iron in their Washington DC collections, additional small samples are scattered across several museums globally.
Recovery Location
The Sardis Iron was discovered near Beaverdam Creek in the northern part of Jenkins County about 200 yards from the Burke County line. Sardis, Georgia in Burke county, is the nearest town. The point of discovery was 6.25 miles west-southwest of Sardis and 11 miles north-northeast of Millen, GA; at an approximate latitude 32°56’56” North and longitude 80°51’54” West as given on the U. S, Geological Survey Map of the Millen quadrangle.
Smithsonian staff visited the site in 1941 accompanied by Mr. Powell, who had led the meteorite’s excavation and recovery. As correctly described by Mr. Powell’s letters there were no visible scars on the surface. The field slopes gently northward from a rounded crest encircled by a 280-foot contour line to the south fork of Beaverdam Creek. The creek is .6 miles away and flows at an altitude of 220 feet above sea level. The meteorite had rested at about 250 feet above sea level, about mid-way between the top of the slope and the creek bed. The 1941 field observations report “there is no indication that this plowed field has eroded very rapidly nor is there any evidence of crater-like depressions.”
Following Mr. Powell’s confident directions; the field team shoveled away about 24” of the weathered, sandy soil to expose the harder surface where the meteorite had rested. This was identified in 1942 as the compact, sandy clay of the Middle Miocene, Hawthorn Formation. However, despite careful observation, nothing was found in the sediments to suggest distortion, depression or disturbance from impact.
The Sardis Iron was discovered near Beaverdam Creek in the northern part of Jenkins County about 200 yards from the Burke County line. Sardis, Georgia in Burke county, is the nearest town. The point of discovery was 6.25 miles west-southwest of Sardis and 11 miles north-northeast of Millen, GA; at an approximate latitude 32°56’56” North and longitude 80°51’54” West as given on the U. S, Geological Survey Map of the Millen quadrangle.
Smithsonian staff visited the site in 1941 accompanied by Mr. Powell, who had led the meteorite’s excavation and recovery. As correctly described by Mr. Powell’s letters there were no visible scars on the surface. The field slopes gently northward from a rounded crest encircled by a 280-foot contour line to the south fork of Beaverdam Creek. The creek is .6 miles away and flows at an altitude of 220 feet above sea level. The meteorite had rested at about 250 feet above sea level, about mid-way between the top of the slope and the creek bed. The 1941 field observations report “there is no indication that this plowed field has eroded very rapidly nor is there any evidence of crater-like depressions.”
Following Mr. Powell’s confident directions; the field team shoveled away about 24” of the weathered, sandy soil to expose the harder surface where the meteorite had rested. This was identified in 1942 as the compact, sandy clay of the Middle Miocene, Hawthorn Formation. However, despite careful observation, nothing was found in the sediments to suggest distortion, depression or disturbance from impact.
The 1942 paper continues to argue “One would suppose that a freely falling body of this size would certainly crush or shatter even an unconsolidated rocks on which it fell. Surely this sandy clay, under the blow of so many thousand square foot pounds, would spatter away. The crater-like scar might not be preserved for an indefinitely long time, but such a depression would last for at least several hundred years. The present owner of the land (never named) has tilled this field for nearly 50 years, and, as the farm belonged to his father, he would almost certainly have heard about it if such a large meteorite had fallen on his farm in the last 75 years.”
But the hardish, sandy-clay surface supporting the meteorite isn’t the Hawthorn Formation, it’s the Altamaha Formation, and it wasn’t Middle Miocene in age, but Early Miocene, say 20 to 23 million years old. (4)
In 1988 Paul F. Huddlestun of the Georgia Geologic Survey, published his updated revision of Georgia’s Miocene sediments. (4) Through extensive fieldwork and a review of the literature he reassigned the Hawthorn Formation as the Hawthorn group and subdivided it into multiple identifiable formations, but none of these ranged as far north as northern Jenkins County. The Hawthorn Group could only be identified at the southern edge of Jenkins County.
But the hardish, sandy-clay surface supporting the meteorite isn’t the Hawthorn Formation, it’s the Altamaha Formation, and it wasn’t Middle Miocene in age, but Early Miocene, say 20 to 23 million years old. (4)
In 1988 Paul F. Huddlestun of the Georgia Geologic Survey, published his updated revision of Georgia’s Miocene sediments. (4) Through extensive fieldwork and a review of the literature he reassigned the Hawthorn Formation as the Hawthorn group and subdivided it into multiple identifiable formations, but none of these ranged as far north as northern Jenkins County. The Hawthorn Group could only be identified at the southern edge of Jenkins County.
However, the Altamaha Formation, also of Miocene age, occurs throughout Jenkins County. It’s a rather hard, iron-rust stained, sandy clay. The sand content is high enough that some of the historic researchers referred to it as the Altamaha Grit. It’s formation is considered to be river related, perhaps as sediments from an estuary.
The Altamaha Formation is devoid of fossils. This poses a problem in dating the sediments. Of all of Georgia’s formations, the Altamaha covers the widest geographic area, but it is also a bit variable. In 1911 Veatch and Stephenson reported oyster shells but a re-examination of the locality by Huddlestun suggests that the oysters came from an underlying formation. In all of the observed locations, Huddlestun could not confidently identify fossils from the Altamaha, there were some possible trace fossils, possible burrows, but Huddlestun couldn’t confidently state that they weren’t more recent backfilled cavities from tree roots.
The Altamaha Formation is devoid of fossils. This poses a problem in dating the sediments. Of all of Georgia’s formations, the Altamaha covers the widest geographic area, but it is also a bit variable. In 1911 Veatch and Stephenson reported oyster shells but a re-examination of the locality by Huddlestun suggests that the oysters came from an underlying formation. In all of the observed locations, Huddlestun could not confidently identify fossils from the Altamaha, there were some possible trace fossils, possible burrows, but Huddlestun couldn’t confidently state that they weren’t more recent backfilled cavities from tree roots.
If you can’t directly date a formation from fossils, the next step is to do so lithologically; or by comparison to other formations. In other words you make observations about the borders of the formation in question. Does it rest on top, underneath, or grade into the neighboring formation? Generally, if it’s on top of a neighboring deposit, it more recent. If it’s underneath, its older. If they grade into each other, they are probably the same age but represent different or changing local conditions. If neighboring formations possess fossils which can aid in dating, so much the better.
Further south the Altamaha Formation grades into the Coosawhatchie Formation which is dated to the Middle Miocene by planktonic fossils. But on the northern Coastal Plain of the Savannah River area, in Jenkins, Burke, and Screven Counties the Altamaha Formation grades into the Tiger Leap Member of the Parachucla Formation of the Hawthorn Group. Planktonic foraminifera fossils of the Tiger Leap Member date these sediments to the Earliest Miocene; say 20 to 23 million years old. (4)
While the author of this page questions the theory that the Sardis Iron fell in the 20-plus million years ago, it is interesting that such a large meteorite ended up resting atop these sediments while leaving no trace of impact evidence despite close observations in 1941. Nor was evidence observed of large-scale erosion. Clearly the Sardis Iron was in place for some time, centuries at least, maybe thousands of years, so how do you get a 1700+ pound iron rock into this position? Could it have been transported by moving water? How was it preserved at all?
This website has seen bountiful evidence of large-scale erosion in Georgia, especially on the Coastal Plain, and moving water, both fresh and saltwater have been responsible at different times.
Further south the Altamaha Formation grades into the Coosawhatchie Formation which is dated to the Middle Miocene by planktonic fossils. But on the northern Coastal Plain of the Savannah River area, in Jenkins, Burke, and Screven Counties the Altamaha Formation grades into the Tiger Leap Member of the Parachucla Formation of the Hawthorn Group. Planktonic foraminifera fossils of the Tiger Leap Member date these sediments to the Earliest Miocene; say 20 to 23 million years old. (4)
While the author of this page questions the theory that the Sardis Iron fell in the 20-plus million years ago, it is interesting that such a large meteorite ended up resting atop these sediments while leaving no trace of impact evidence despite close observations in 1941. Nor was evidence observed of large-scale erosion. Clearly the Sardis Iron was in place for some time, centuries at least, maybe thousands of years, so how do you get a 1700+ pound iron rock into this position? Could it have been transported by moving water? How was it preserved at all?
This website has seen bountiful evidence of large-scale erosion in Georgia, especially on the Coastal Plain, and moving water, both fresh and saltwater have been responsible at different times.
Related Research
Ed Albin, who’s mentioned earlier in this piece, has had a long-standing interest in meteorites and georgiaites. (For info on georgiaites see sections 14B & 14J of this website.) In the late 1990s he was a researcher and educator at Fernbank Science Center in Atlanta and published several papers on georgiaites including one that showed the bulk of Georgia’s tektites, or georgiaites, came from the Altamaha formation, though they’re much older than the Altamaha. (5)
His report was also on the northern Altamaha beds dated to the Early Miocene. The small glass georgiaites date to (roughly) 34 million years old. They are Late Eocene, yet they’re found in 10 to 15 million-year-old beds of the northern Altamaha Formation. (They’re also found in the younger Altamaha beds further south.) The glass georgiaites weathered out of the Late Eocene sediments, and were transported by moving waters, probably during the Miocene. In several places the Altamaha Formation has of rounded quartz pebbles (gravel) of about the same size as the georgiaites, gravel which could have easily ground the tektites to dust, but they didn’t.
While the natural glass tektites are chemically more stable than iron, an iron meteorite could endure rough transportation better than a small glass tektite. I’m certainly not arguing that the Sardis is as old as the georgiaites, but flowing water can move large rocks more easily than most of us imagine. So it’s not impossible that weathering transported the Sardis to it final resting place on top of the Altamaha Formation, it wouldn’t even have to move it very far and the Altamaha might well have been in place when it happened.
Ed Albin, who’s mentioned earlier in this piece, has had a long-standing interest in meteorites and georgiaites. (For info on georgiaites see sections 14B & 14J of this website.) In the late 1990s he was a researcher and educator at Fernbank Science Center in Atlanta and published several papers on georgiaites including one that showed the bulk of Georgia’s tektites, or georgiaites, came from the Altamaha formation, though they’re much older than the Altamaha. (5)
His report was also on the northern Altamaha beds dated to the Early Miocene. The small glass georgiaites date to (roughly) 34 million years old. They are Late Eocene, yet they’re found in 10 to 15 million-year-old beds of the northern Altamaha Formation. (They’re also found in the younger Altamaha beds further south.) The glass georgiaites weathered out of the Late Eocene sediments, and were transported by moving waters, probably during the Miocene. In several places the Altamaha Formation has of rounded quartz pebbles (gravel) of about the same size as the georgiaites, gravel which could have easily ground the tektites to dust, but they didn’t.
While the natural glass tektites are chemically more stable than iron, an iron meteorite could endure rough transportation better than a small glass tektite. I’m certainly not arguing that the Sardis is as old as the georgiaites, but flowing water can move large rocks more easily than most of us imagine. So it’s not impossible that weathering transported the Sardis to it final resting place on top of the Altamaha Formation, it wouldn’t even have to move it very far and the Altamaha might well have been in place when it happened.
Unanswered Questions for the Sardis Iron
There are almost more unanswered questions around the Sardis Iron than there are facts…
It may be that these questions cannot be answered. Science is ever the pursuit of knowledge, it is a journey, not a destination.
There are almost more unanswered questions around the Sardis Iron than there are facts…
- Just when might the Sardis Iron have fallen?
- Was it transported into the position of discovery?
- At what rate has it weathered?
- Is it even remotely possible that an iron, so amazingly suspectable to weathering, could have endured buried in sandy clay for millennia?
It may be that these questions cannot be answered. Science is ever the pursuit of knowledge, it is a journey, not a destination.
Georgia Backroads Spring 2023 artcle pdf file.
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References
- E. P. Henderson & A. S. Furcron; Meteorites in Georgia, Georgia Geological Survey, 1966
- E. P. Henderson & C. Wythe Cooke; The Sardis (Georgia) Meteorite, Proceedings of the United States National Museum, Smithsonian Institution, Vol. 92, No. 3143, 1942
- David Boehnlein, The Story of Fossil Meteorites, Astronomy, 29/November/2017
- Huddlestun, Paul F; The Miocene Through Holocene, A Revision of the Lithostratigraphic Units of the Coastal Plain of Georgia, Georgia Geologic Survey, 1988
- Albin, Ed; Redistribution of Georgia Tektites as Channel Lag Deposits; Dept of Space Science, Fernbank Science Center, Lunar and Planetary Sciences XXVIII, 1996