art Posted July 11, 2009 Share Posted July 11, 2009 During a recent foray I found a pyrite that had two colors of crystals. A small part of it was the normal brassy color, and the rest had the same crystal structure except it was silver in color. Is this a common variation? Link to comment Share on other sites More sharing options...
Guest N.AL.hunter Posted July 11, 2009 Share Posted July 11, 2009 Could it be galena? Link to comment Share on other sites More sharing options...
art Posted July 11, 2009 Author Share Posted July 11, 2009 Could it be galena? Looked a image up- very similar. Would one find both minerals together? The crystals look like they did a color change in the same bed. http://www.sciencehelpdesk.com/img/bg3_6/Galena.jpg Link to comment Share on other sites More sharing options...
Frank Menser Posted July 11, 2009 Share Posted July 11, 2009 That is not an uncommon occurance. Another possibility is a change in the chemical composition in the Pyrite by the presence of another metal. Copper and gold are frequently found in pyrite and to an extent can influence the color. Could you post a picture? Be true to the reality you create. Link to comment Share on other sites More sharing options...
Shamalama Posted July 11, 2009 Share Posted July 11, 2009 Marcasite can be silvery colored and sometimes form cubes. can you post a pic? Oh, test the silver crystals with a nail, if the nail scratches the cubes then it's probably Galena. -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...
art Posted August 4, 2009 Author Share Posted August 4, 2009 Soooo, this crystal cluster has been sitting in front of my keyboard since I first posted about it, and it developed a fracture- just sitting there. I picked it up, and it broke in half. Then it just started to crumble over the next few days. The thing is turning to dust before my very eyes.......... Link to comment Share on other sites More sharing options...
art Posted August 4, 2009 Author Share Posted August 4, 2009 Marcasite can be silvery colored and sometimes form cubes. can you post a pic? Oh, test the silver crystals with a nail, if the nail scratches the cubes then it's probably Galena. I tried to post pics of other fossils I have, and the camera just isn't up to it. Link to comment Share on other sites More sharing options...
2ynpigo Posted August 4, 2009 Share Posted August 4, 2009 Marcasite specimens, iron sulfide, will often decay to a pile of white powder. Link to comment Share on other sites More sharing options...
tracer Posted August 4, 2009 Share Posted August 4, 2009 Marcasite specimens, iron sulfide, will often decay to a pile of white powder. big time Link to comment Share on other sites More sharing options...
art Posted August 4, 2009 Author Share Posted August 4, 2009 How can they last so long in the ground, and decay in a couple months. Moisture? Link to comment Share on other sites More sharing options...
bigjohn835 Posted August 4, 2009 Share Posted August 4, 2009 Here's a galena pic or two With rocks in my head, and fossils in my heart.... Link to comment Share on other sites More sharing options...
art Posted August 4, 2009 Author Share Posted August 4, 2009 Here's a galena pic or two Looks pretty close to what I "used" to have. Link to comment Share on other sites More sharing options...
Mike Owens Posted August 4, 2009 Share Posted August 4, 2009 big time Amen! I have several boxes with powder reeking of sulphur odor. Use to be marcasite. -----"Your Texas Connection!"------ Fossils: Windows to the past Link to comment Share on other sites More sharing options...
2ynpigo Posted August 4, 2009 Share Posted August 4, 2009 I should also mention that some pyrite is also readly subject to decay. I would guess that the microbes that are involved in causing the decay do better in an oxygen enriched environment, but this is only a guess. You could probably google an answer to your question that carries more credibility than my guess. Link to comment Share on other sites More sharing options...
art Posted August 4, 2009 Author Share Posted August 4, 2009 Amen! I have several boxes with powder reeking of sulphur odor. Use to be marcasite. It does have a slight sulfur odor...not real pleasant, now that you mention it. Link to comment Share on other sites More sharing options...
Auspex Posted August 4, 2009 Share Posted August 4, 2009 It does have a slight sulfur odor...not real pleasant, now that you mention it. Sulfuric acid; keep it well away from anything you like having around! "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
art Posted August 4, 2009 Author Share Posted August 4, 2009 Google result.... http://www.galleries.com/minerals/sulfides...it/marcasit.htm Link to comment Share on other sites More sharing options...
tracer Posted August 4, 2009 Share Posted August 4, 2009 i've actually gotten to see large amounts of this stuff in varying stages, from "new" and shiny, to powder, because it lives near me, kinda. i personally just can't collect anything made of these unstable minerals, even if they are cool. i mean, i've got a few small pyritized things, but i think most of them had sharp edges on them that stuck on my clothes and rode home on me or something. i'm allergic to oxidation and consider it second only to taxation in annoyance factor. if you wish to be depressed, google "pyrite rot" or "pyrite disease" and start reading about it. i'm telling you, folks, it's right up there with tooth decay as far as fun goes. <shouting very loudly> WHEN PYRITE IS OUTLAWED, ONLY OUTLAWS WILL OWN PYRITE!!! wow. um, sorry. i don't have many pet peeves, but the ones i do have are doozies, i guess. Link to comment Share on other sites More sharing options...
2ynpigo Posted August 4, 2009 Share Posted August 4, 2009 Marcasite and pyrite from some localities are quite stable. For example, many marcasite specimens from the Tr-State district have survived decades without decay. I have pyrite specimens that have been in my collection for 20 plus years and they are just as nice as when I first got them. Link to comment Share on other sites More sharing options...
usaman65 Posted August 4, 2009 Share Posted August 4, 2009 Ill go with Arsenopyrite. It has a silver color. kev Link to comment Share on other sites More sharing options...
New Members matthew1987 Posted February 25, 2015 New Members Share Posted February 25, 2015 this looks like the same pyrite or ore you were talking about. the streaking is blackish and was found with normal pyrite. Link to comment Share on other sites More sharing options...
New Members matthew1987 Posted February 25, 2015 New Members Share Posted February 25, 2015 this looks like the same pyrite or ore you were talking about. the streaking is blackish and was found with normal pyrite. IMG_1256.JPG this has not crumbled have had it for a year Link to comment Share on other sites More sharing options...
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