Red_desert 138 Posted November 29, 2011 Share Posted November 29, 2011 On my recent trip to Arkansas, found this jasper that looks almost like agate, with a yellowish lightening bolt shape running through it.I've seen heart pendants on the Internet cut from similar jasper.Has a texture more like quartz or agate.The geologist at the diamond crater said it's jasper. Link to post Share on other sites
hcc 0 Posted November 29, 2011 Share Posted November 29, 2011 On my recent trip to Arkansas, found this jasper that looks almost like agate, with a yellowish lightening bolt shape running through it.I've seen heart pendants on the Internet cut from similar jasper.Has a texture more like quartz or agate.The geologist at the diamond crater said it's jasper. Nice. Looks a little bit like what I found recently. See my post "Help me identify green rock" a day or two before yours. Except your red streaks look integral to the hard portions of the rock whereas mine are a different material, duller and rougher. Link to post Share on other sites
Goldfinger 43 Posted November 29, 2011 Share Posted November 29, 2011 Personally I think it's more of an agate then a jasper. From the photos, it seems to be somewhat translucent where it flakes which is a property a true jasper wouldn't have.Steve Link to post Share on other sites
Red_desert 138 Posted November 29, 2011 Author Share Posted November 29, 2011 Personally I think it's more of an agate then a jasper. From the photos, it seems to be somewhat translucent where it flakes which is a property a true jasper wouldn't have.SteveI know what you mean, some rocks took to be identified at the crater, felt on the surface like quartz stones we find here in the glacial drift deposits. The geologists there always said the stones are jasper. Some on the surface look and feel like agate or quartz, others real oily or like caramel candy...but inside usually a different color, look more like agate. I've got some photos taken of a few collected specimens, post them soon. Link to post Share on other sites
Red_desert 138 Posted November 29, 2011 Author Share Posted November 29, 2011 Fractured piece with the surface feels like a quartz stone, inside had to make sure it wasn't a deep colored amethyst.Another dark on surface, but not fractured.Many different color variations, some browwn surface with inside light yellow or dark as this one.Most of these jasper specimens came from the SW corner of the mine field, plenty of good stones free of pitting or folding cracks. Link to post Share on other sites
Red_desert 138 Posted November 29, 2011 Author Share Posted November 29, 2011 Plain brownish on the surface, entirely different center.Luster surface type.The light area on the side is a reflection from the dime. Many of these I had checked out at the mineral ID counter by the geologists. Opal is mentioned in the Arkansas Diamond book printed in the 1990s by Terry. If I've got one you think is opal, let me know. The opal pieces in the book photo were whitish. Link to post Share on other sites
Goldfinger 43 Posted November 30, 2011 Share Posted November 30, 2011 Any opal from that area would be just plain common opal. The closest thing you have that resembles it is that 5th picture down that has the light brown exterior with the whitish interior..Steve Link to post Share on other sites
Bedrock Bob 3,891 Posted November 30, 2011 Share Posted November 30, 2011 Everything you have here is a silicate. Microcrystalline and cryptocrystalline silicon dioxide. As far as I know there are no differences between "jasper" and "agate"..."Jasper" is the red phase of agate and is often microcrystalline (glassy) rather than cryptocrystalline (sugary)...Or do I have that backwards?Anyhoo, it is all silicon dioxide, and cryptocrystalline. Common phases of silica formed at mid temp/pressure/depth. Silica at depth formes big drusy quartz crystals (intrusive, high depth/temp/press), at mid range forms smaller crystals, and near the surface forms sugary agate and glassy jaspers, chalsedony and opal. You are in posession of the sugary form of silicon dioxide crystal formed in rocks that cooled near the surface. Opal is glass. Same stuff, silicon dioxide, with water back. Formed at zero pressure. You dont have any there. It generally is white and looks almost like bone. Now, that silica can form as a result of hot solution or replacement and that is a story for another day. Replacement is where the precious stuff is formed. Common agates are generally a result of hot solution rather than replacement. Link to post Share on other sites
Red_desert 138 Posted December 1, 2011 Author Share Posted December 1, 2011 Both jasper and agates are cryptocrystalline quartz, what they call agate at the crater, gets it's color from sandstone or might be formed in he sandstone. Usually is flat, can be found in tailing piles along with sandstone.Here is a light colored jasper.When collecting them, all look about the same....get photos, after cleaned up good, endless variety of colors or patterns. Link to post Share on other sites
Red_desert 138 Posted December 1, 2011 Author Share Posted December 1, 2011 Great place for jasper collecting anyway....you won't run out of possibilities.Most of what I collected are smaller, but seen nice stones large enough for book shelves, use for bookends, left those rocks behind, watching my weight load.This one the color goes from surface through the stone. Link to post Share on other sites
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