Mediospirifer Posted January 29, 2014 Share Posted January 29, 2014 Last month, my husband found this piece labeled "Hematite After Wood Minnesota" at a rock shop. The piece is about 7 cm long by 2 cm wide between the bulges. I have some doubts about the "After Wood" part of this label. The bulges look more botryoidal than barklike, and I don't see any distinctive woodlike structure on the broken ends. I could easily be wrong, though. Here are some better-illuminated pictures: Do I have a really cool mineral replacement fossil here, or a really wild-looking pseudofossil? If the former, I'll include it in my mineral club open house display this Sunday. If the latter, I might include it in a mineral club display on pseudofossils next year! Link to comment Share on other sites More sharing options...
Herb Posted January 29, 2014 Share Posted January 29, 2014 I don't see a fossil there, but it has some nice crystal structure, It does look like hematite in the picture. "Absence of evidence is not evidence of absence"_ Carl Sagen No trees were killed in this posting......however, many innocent electrons were diverted from where they originally intended to go. " I think, therefore I collect fossils." _ Me "When you have eliminated the impossible, whatever remains, however improbable, must be the truth."__S. Holmes "can't we all just get along?" Jack Nicholson from Mars Attacks Link to comment Share on other sites More sharing options...
Taogan Posted January 29, 2014 Share Posted January 29, 2014 Nice specimen of haematite. It was described as "after" which could be taken as meaning "looks like" but doesn't imply any more than a passing resemblance. Link to comment Share on other sites More sharing options...
Shamalama Posted January 29, 2014 Share Posted January 29, 2014 Definitely a pseudofossil. Looks like botryoidal Hematite or possibly Goethite. The latter is found here in Pennsylvania among heavily oxidized iron deposits called "Bog Ore" where is forms large hollow geodes called "bombs" (since they sometimes look like rusted WWII bombs I assume). Here is a page with specimens that look similar to yours from Minniesota and some Pennsylvania stuff too. -Dave __________________________________________________ Geologists on the whole are inconsistent drivers. When a roadcut presents itself, they tend to lurch and weave. To them, the roadcut is a portal, a fragment of a regional story, a proscenium arch that leads their imaginations into the earth and through the surrounding terrain. - John McPheeIf I'm going to drive safely, I can't do geology. - John McPheeCheck out my Blog for more fossils I've found: http://viewsofthemahantango.blogspot.com/ Link to comment Share on other sites More sharing options...
Mediospirifer Posted January 30, 2014 Author Share Posted January 30, 2014 Thanks, guys! That's pretty much what I was thinking. My husband is disappointed, though. Neither of us have heard of "X after Y" terminology being applied to something where "Y" was never present in the first place. I thought it was possible that the seller had misidentified it. There were a few other things with odd labels for what they were, including a nice piece of tree fern fossil labeled as "Kingston Lode Ore"! I figured someone on TFF could settle the question for this one. It's an excellent specimen of hematite or goethite, and I'm not disappointed with the price of it. Link to comment Share on other sites More sharing options...
Wrangellian Posted January 30, 2014 Share Posted January 30, 2014 It is my understanding that "X after Y" does denote a replacement, at least in the mineral world. So it sounds like someone misidentified something (in part).. happens all the time! Link to comment Share on other sites More sharing options...
Taogan Posted January 30, 2014 Share Posted January 30, 2014 It is my understanding that "X after Y" does denote a replacement, at least in the mineral world. So it sounds like someone misidentified something (in part).. happens all the time! I think what we have is a mix up in terminology between disciplines, in antiques, where it is fairly commonly used, "X after Y" is used to mean looks like, not replaced by. I sometimes think we should simplify the English language. Link to comment Share on other sites More sharing options...
Wrangellian Posted January 30, 2014 Share Posted January 30, 2014 I think what we have is a mix up in terminology between disciplines, in antiques, where it is fairly commonly used, "X after Y" is used to mean looks like, not replaced by. I sometimes think we should simplify the English language. I'm sure there are some things that could be simplified, but I think within each discipline things are generally simple (because they're already complex enough that nobody would want to add unneeded complexity to it), even if it's not the same usage as in other disciplines - so trying to make a 'grand unified' system for all of them might make the whole thing way too complicated for anybody to understand because it has to deal with everything under the sun rather than with just those few things dealt with by a given discipline. Hmmm.. As usual my way of describing things is probably unnecessarily complicated! Link to comment Share on other sites More sharing options...
painshill Posted January 30, 2014 Share Posted January 30, 2014 There was dicsussion on another thread recently about fossil pseudomorphs. The "X after Y" terminology in the mineral world generally refers specifically to a situation where the second mineral has taken on a crystal shape which is not one of its natural crystal forms. Generally that happens when the second mineral occupies a void left behind by the first mineral and is "forced" to adopt that shape. The term has however been extended to cover "[mineral] after [organic fossil]". There are a few examples here on the mindat site of minerals "after shell" and "after wood". http://www.mindat.org/forum.php?read,82,207457,page=1 I would agree that the example being shown here is not that kind of pseudomorph. Roger I keep six honest serving-men (they taught me all I knew);Their names are What and Why and When and How and Where and Who [Rudyard Kipling] Link to comment Share on other sites More sharing options...
Taogan Posted January 30, 2014 Share Posted January 30, 2014 Classic case of technical usage and common usage of the language not matching. Not the first time I've seen this and it won't be the last. Link to comment Share on other sites More sharing options...
Mediospirifer Posted January 30, 2014 Author Share Posted January 30, 2014 Thanks, guys! I'm glad there's a consensus. This piece will be on display at our mineral club open house on Sunday, but not as part of my fossil types display. I'll offer it to one of my fellow club members for her table of crystal shapes. Sunday, Feb. 2. 1-5 PM at the Museum of the Earth in Ithaca, NY, if any nearby TFF members want to check it out. That's the Museum's Free Day, so there won't be any admission charge. The Museum is well worth visiting! The discussion of language differences between disciplines reminds me of how confusing I found the term "double-blind" in my different science classes. That meant something different in sociology than it does in biology or psychology! Link to comment Share on other sites More sharing options...
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