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Post by woodman on Sept 3, 2016 14:41:12 GMT -5
I was wonder what could have caused the indentations in this 5/3 piece of agate. Salt? then dissolved?  |
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Post by captbob on Sept 3, 2016 15:07:18 GMT -5
Kinda cool. Maybe calcite crystals that dissolved?
Where is it from?
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Post by woodman on Sept 3, 2016 15:10:15 GMT -5
Kinda cool. Maybe calcite crystals that dissolved? Where is it from? I an going to assume Oregon, but not sure. |
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Deleted
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Post by Deleted on Sept 3, 2016 15:16:35 GMT -5
Pyrite
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Post by captbob on Sept 3, 2016 15:44:03 GMT -5
I wondered the same at first too Scott, that's why I asked where it was found. I have never seen such well shaped cubes of pyrite from Oregon. Usually more in the pyritohedron shape, - at least more sides than just a cube. Have you seen/found cubed pyrite up in that area? Anything of a decent size? What size is that rock woodman ? |
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Post by Deleted on Sept 3, 2016 15:55:25 GMT -5
I wondered the same at first too Scott, that's why I asked where it was found. I have never seen such well shaped cubes of pyrite from Oregon. Usually more in the pyritohedron shape, - at least more sides than just a cube. Have you seen/found cubed pyrite up in that area? Anything of a decent size? What size is that rock woodman ? Nope. Never been to Oregon except to get pissed waiting for a high school dropout to pump my gas and get up to Seattle. The cubes are so perfectly formed and the "twinned" one looks exactly like a pyrite I have in my drawer. |
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Post by woodman on Sept 3, 2016 16:20:22 GMT -5
I wondered the same at first too Scott, that's why I asked where it was found. I have never seen such well shaped cubes of pyrite from Oregon. Usually more in the pyritohedron shape, - at least more sides than just a cube. Have you seen/found cubed pyrite up in that area? Anything of a decent size? What size is that rock woodman 5" by 3" I first thought pyrite but then thought they would still be there. This the problem when you buy a pile of rocks at an estate sale. Most all in the pile were from Oregon, but would not bet on it. I am thinking about cutting it and see if anything is on the inside. |
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Post by fernwood on Sept 3, 2016 17:47:40 GMT -5
Interesting.
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Post by jakesrocks on Sept 3, 2016 18:43:43 GMT -5
Possibly fluorite, but don't know if fluorite is found in Oregon.
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Post by Deleted on Sept 4, 2016 10:24:48 GMT -5
Possibly fluorite, but don't know if fluorite is found in Oregon. Good call. I thought fluorite was those double tetrahedrons. Today I learn that it cubes too! Thanks Don. Woodman is not sure of origin. So, fluorite or pyrite are likely culprits. |
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Post by captbob on Sept 4, 2016 12:30:42 GMT -5
And calcite is more likely than either.
Guess we will never know.
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gemfeller
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Post by gemfeller on Sept 4, 2016 13:16:33 GMT -5
Cubic: three axes of equal length intersecting each other at 90 degrees. While a standard cube is one possible habit, cubic (isometric)crystals can assume a number of different forms. There are at least 144 different cubic minerals known, including diamonds, spinels, garnets, fluorite, pyrite etc. Cubic crystal habits:  Calcite crystals are trigonal-rhombohedral, not cubic. I'm no crystallographer -- I suck at geometry -- and it's hard for me to tell exactly what crystal system is represented in the specimen. I think it would take some careful study with calipers and other instruments to be sure what the dissolved crystal system might have been. |
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Post by Deleted on Sept 4, 2016 18:04:11 GMT -5
And calcite is more likely than either. Guess we will never know. Calcite comes naturally in cubes? Rhombs (6 sided solid, no right angles) sure. But cubes? Your final thought is spot on. We will never know for certain. Well, it ain't diamond...... |
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Post by Deleted on Sept 4, 2016 18:14:52 GMT -5
 Badass calcite in rutilated quartz |
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Fossilman
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Post by Fossilman on Sept 4, 2016 19:13:24 GMT -5
I was wonder what could have caused the indentations in this 5/3 piece of agate. Salt? then dissolved? I have a few quartz agates like this/found in our local creek,in the mountains...Mine are white... |
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Nov 15, 2024 17:44:51 GMT -5
Nov 15, 2024 17:44:51 GMT -5
