diggumdave Posted August 4 Share Posted August 4 I was on a river trip for petrified wood this morning when I found this piece of burnt wood (not petrified) sticking out of the upper portion of the miocene layer, and it’s got pyrite growing on it. Cracks in the end grain are filled with pyrite as well. I’ve never seen this before and i’ve been collecting in Texas for 20+ years. Is this something to get excited about? Also, how do I classify this wood? Fossilized?Preserved?Coalified? I can poke a fingernail into it and I’m fairly sure it will burn once it dries out. it just looks and feels like plain old burnt wood. more pics below. thanks, dave …but i’ve been wrong before. Link to comment Share on other sites More sharing options...
Ludwigia Posted August 4 Share Posted August 4 This is fascinating. Are there any coal deposits in the area? Greetings from the Lake of Constance. Roger http://www.steinkern.de/ Link to comment Share on other sites More sharing options...
Rockwood Posted August 4 Share Posted August 4 17 minutes ago, Ludwigia said: This is fascinating. Are there any coal deposits in the area? We're looking at one. Lignite. 2 Link to comment Share on other sites More sharing options...
ynot Posted August 4 Share Posted August 4 Because of the iron and sulphur that are in living plants, Pyrite is a common occurrence in coal deposits. 1 Link to comment Share on other sites More sharing options...
Rockwood Posted August 4 Share Posted August 4 The decomposing organic matter uses up oxygen that would otherwise turn it into rust and stink. Link to comment Share on other sites More sharing options...
Rockwood Posted August 4 Share Posted August 4 Be advised that lignite can become quite unstable when it dries. 1 Link to comment Share on other sites More sharing options...
diggumdave Posted August 4 Author Share Posted August 4 Thanks so much! There are coal deposits all over the river, i assume from an ancient fire, but usually they are higher up the hill. It’s waterlogged now and i’m hoping it doesn’t fall apart once it dries… any suggestions for preservation? …but i’ve been wrong before. Link to comment Share on other sites More sharing options...
ynot Posted August 4 Share Posted August 4 31 minutes ago, diggumdave said: , i assume from an ancient fire, Not from a fire, just buried and pressurized. 1 1 Link to comment Share on other sites More sharing options...
Rockwood Posted August 4 Share Posted August 4 I think butvar is the preferred preservative. Super glue will suffice, or Elmer's glue diluted by an equal part water will also work. Elmer's is permanent and can yellow with age. Link to comment Share on other sites More sharing options...
JohnJ Posted August 5 Share Posted August 5 7 hours ago, diggumdave said: I’ve never seen this before and i’ve been collecting in Texas for 20+ years. Is this something to get excited about? You've found a very nice example; but where you find samples of "coalified" wood in Texas, pyritized pieces are more common. The human mind has the ability to believe anything is true. - JJ Link to comment Share on other sites More sharing options...
hemipristis Posted August 5 Share Posted August 5 5 hours ago, Rockwood said: I think butvar is the preferred preservative. Super glue will suffice, or Elmer's glue diluted by an equal part water will also work. Elmer's is permanent and can yellow with age. 6 hours ago, diggumdave said: Thanks so much! There are coal deposits all over the river, i assume from an ancient fire, but usually they are higher up the hill. It’s waterlogged now and i’m hoping it doesn’t fall apart once it dries… any suggestions for preservation? OP--best make it fast. the wood will dry out, and the pyrite/marcasite will degrade into iron oxides and sulfur very rapidly 2 'Those who cannot remember the past are condemned to repeat it.' George Santayana Link to comment Share on other sites More sharing options...
DPS Ammonite Posted August 5 Share Posted August 5 21 minutes ago, hemipristis said: OP--best make it fast. the wood will dry out, and the pyrite/marcasite will degrade into iron oxides and sulfur very rapidly Keep it dry. Sulphuric acid can form too which eats paper labels and stinks. https://vertpaleo.org/wp-content/uploads/2021/03/Shinya_and_Bergwall_2007.pdf 1 My goal is to leave no stone or fossil unturned. See my Arizona Paleontology Guide link The best single resource for Arizona paleontology anywhere. Link to comment Share on other sites More sharing options...
hemipristis Posted August 5 Share Posted August 5 55 minutes ago, DPS Ammonite said: Keep it dry. Sulphuric acid can form too which eats paper labels and stinks. https://vertpaleo.org/wp-content/uploads/2021/03/Shinya_and_Bergwall_2007.pdf Best to add the butter as soon as possible, and not let the specimen dry out completely or it will fall apart 'Those who cannot remember the past are condemned to repeat it.' George Santayana Link to comment Share on other sites More sharing options...
FranzBernhard Posted August 5 Share Posted August 5 Best preserved in a bucket with water. Lignite is usually falling apart when drying and pyrite in association with coal is usually also very unstable and gives lots of iron sulfate bloom (with volume gain) and sulfuric acid when oxygenated. In other words, its a preservational nightmare. Franz Bernhard Link to comment Share on other sites More sharing options...
diggumdave Posted August 6 Author Share Posted August 6 Wow there’s tons of stuff on here about preservation. I know where to find the lignite now so I’ll be able to try different things and i’ll post when it’s done. Thanks again😉 …but i’ve been wrong before. Link to comment Share on other sites More sharing options...
Rockwood Posted August 6 Share Posted August 6 Let some dry out. The results can be interesting as long as it's expected. Link to comment Share on other sites More sharing options...
EMP Posted August 6 Share Posted August 6 I found a bunch of lignified wood logs like this from the Cretaceous of Maryland, and tried experimenting a few times with different preservation techniques. Since I didn’t have access to fancier stuff, my first method was placing the specimen in a tub of water and Elmer’s white glue mix, roughly 50-50, and letting it soak. That worked a little bit but takes a while for it to soak through, and can cause problems if it doesn’t. I tried upping the glue concentration but didn’t get much better results. Finally I ended up just painting straight Elmer’s glue onto the specimen, applying new coats every hour or so until I was satisfied it was thoroughly coated, making sure to get in all of the cracks and crevices. I would let each coat dry to what an engineer might call a “saturated surface dry” condition - basically that it has a sheen but the glue isn’t forming globs or anything on the surface. I then let it dry in a cool, dark space in my basement for a period of roughly 24 hours, checking on it to see if anything was going awry. After that time the glue had settled in and the specimen was pretty much intact, to my surprise if I’m being honest. I’ve noticed some drying out since in hard to reach crevices where the glue was thin which I’ll have to patch up, but overall a surprisingly effective method. The only real downside is it gives the specimen a coated, plastic-y look to it, but personally I don’t mind. I’ve heard the coat can also yellow over time but honestly I don’t think that’d matter much with a chunk of lignite. If it dries out there might be amber inside, and so there might be a silver lining to losing the lignite. At least with my Maryland specimens I’ve found a few pieces of amber that way, and that was a bit of a consolation. 1 Link to comment Share on other sites More sharing options...
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