Fossil Diver Steve Posted November 24, 2012 Share Posted November 24, 2012 Hi everyone, I hope it's ok that I post this here, but my question is not necessarily fossil related but about a rock I found while looking for fossils. We were hunting a road cut in Indiana, and as soon as I got out of my truck I spotted an odd stone on the ground. I picked it up and immediately could tell it was much heavier than it looked. It is a brown color with green oxidation on, it appears, the sides that were exposed. When I got home, I put a magnet too it and it turns out to be very magnetic. Through the research I have done, I am thinking it is an Iron/Nickel mix but I'm not familiar with what either really look like. It also has some yellow crystal formations on it. Can anyone help me positively identify what this is? Here are a series of pictures. Thank you in advance for your help. Link to comment Share on other sites More sharing options...
painshill Posted November 25, 2012 Share Posted November 25, 2012 It’s a nickel ore of the type generally known as “garnierite”, although that name isn’t accepted by the Mineral Nomenclature Committee because it doesn’t have a precisely defined composition: http://www.hiwtc.com/products/nickel-ore-1563-21544.htm Also known generically as “nickel laterite”. These ores have a high proportion of nickel oxide and usually a fair amount of iron as well. 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...
Fossil Diver Steve Posted November 25, 2012 Author Share Posted November 25, 2012 Thank you painshill! I appreciate the information. Can you tell me if this is rare, or if it is common? Thanks again! Link to comment Share on other sites More sharing options...
painshill Posted November 25, 2012 Share Posted November 25, 2012 No, it’s not rare… but perhaps rarely exposed - except in areas where it has been mined. When lateritic deposits occur they are normally in very large sheets but since they are derived from the upper mantle they aren’t normally near the surface. Garnierite occurs by weathering of those rocks when they are exposed. There are large lateritic sheets running NE-SE of Indiana with garnierite reported (but not confined to) these areas: [pic from Mindat] 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...
Fossil Diver Steve Posted November 26, 2012 Author Share Posted November 26, 2012 Thank you, you certainly know your stuff! Link to comment Share on other sites More sharing options...
Recommended Posts