adrian65
Cave Dweller 
Arch to golden memories and to great friends.
Member since February 2007
Posts: 10,790
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Post by adrian65 on Apr 9, 2009 10:53:57 GMT -5
Jason, Awesome stuff!! The trick is in the orientation and cutting or else it just becomes obsidian!!! What is it that gives it the color it shows...always wondered?? Larry Could be as same as opal? Some water content? Or maybe microscopic bubbles, or maybe oriented micro-fractures? Adrian |
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rockhound97058
freely admits to licking rocks
Thundereggs - Oregons Official State Rock!
Member since January 2006
Posts: 760
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Post by rockhound97058 on Apr 10, 2009 0:01:59 GMT -5
I'm unsure what the exact inclusion is.... I know it's not moisture such as your opals would contain. I believe its more of a mineral based thing? Can't answer for sure....Great question  ---- OK you got me curious! I did a search on the net and here's one answer I found regarding the fire obsidian. Fire obsidian - iridescent obsidian from Glass Buttes, Oregon; "fire" is said to be due to reflection of light off thin layers the refractive indices of which are higher than the rest of the obsidian because of their containing extremely small (nanometric) magnetite crystals |
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Gem'n I
freely admits to licking rocks
Member since March 2008
Posts: 980
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Post by Gem'n I on Apr 10, 2009 16:45:41 GMT -5
Jason,
You have to watch those refractive indices...I kinda thought that maybe what it was until I saw your pic of number 3 which looks totally outrageous in pattern and blows my thoughts of refraction...you see the same type of pattern in clear glass when you get a stone nick in your windshield and see that rainbow effect in the dimple...but the patterns of this stuff blows my mind....!!
Treasure Channel just did a piece on rainbow obsidian in the Madoc Forest?? What was interesting was the obsidian they found was all the flavors grouped in a very random order...mahogany next to silver sheen next to rainbow...no real pattern...that just led me to thinking how does this happen???
Larry
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Post by fishenman on Apr 10, 2009 19:20:29 GMT -5
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---- OK you got me curious! I did a search on the net and here's one answer I found regarding the fire obsidian.
Gotta lick those rocks to see if they shine!!
