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Select Stones, Cabochon Special Edition
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Author:  ROM [ Thu Dec 09, 2010 11:38 pm ]
Post subject:  Re: Select Stones, Cabochon Special Edition

Swishman wrote:
Blue Opal from a one hit vein in Virgin Valley, not sure if any more has been found or not yet. I am under the belief that it is the same mineral/opal belt that extends all the way into the blue opal areas in Oregon as well.

Yes, it's the same opal belt. I don't know about the VV blues which you say are vein-type but the Idaho/Oregon blue opalite occurs inside thundereggs, some very large. It's marketed as Owyhee Blue Opal. Opal of all kinds including some with fantastic color play is found in the Owyhees around Marsing, ID but it's very cracky, just like the VV material.

Nice stones everyone! There's a tremendous amount of natural beauty in cabochon gems and they usually tell fascinating geological tales as well. Sometimes the patterns are the story, as with this ironstone opal from Koroit in Australia's Queensland. This stone has a bit of color-play opal but I cut it because the patterns are so strongly suggestive of Australian Aboriginal art.

Attachments:
OP 78.JPG
OP 78.JPG [ 36.55 KiB | Viewed 950 times ]

Author:  Jason [ Thu Dec 09, 2010 11:58 pm ]
Post subject:  Re: Select Stones, Cabochon Special Edition

Here's an enormous Turkish blue chalcedony cushion shaped cab. Measures 36x36x19 mm and weighs 207cts.

[swf]http://i677.photobucket.com/albums/vv131/selectgem/bluechalced.swf,360,280[/swf]

Author:  mehoose [ Fri Dec 10, 2010 12:08 am ]
Post subject:  Re: Select Stones, Cabochon Special Edition

Think my finger would drop off wearing that Jason. Gorgeous shading.

Some beauties there Jamey and ROM, gotta love the Koroits...and the Yowah's.

Author:  Stonebender [ Fri Dec 10, 2010 4:09 am ]
Post subject:  Re: Select Stones, Cabochon Special Edition

ROM wrote:
Nice stones everyone! There's a tremendous amount of natural beauty in cabochon gems and they usually tell fascinating geological tales as well. Sometimes the patterns are the story, as with this ironstone opal from Koroit in Australia's Queensland. This stone has a bit of color-play opal but I cut it because the patterns are so strongly suggestive of Australian Aboriginal art.


Gorgeous. Very nice. I'd love to get my hands on some of that nice material. All I seem to be able to find is just junk. I'd love to find a piece that will cut me some "church windows".

Swishman wrote:
Blue Opal from a one hit vein in Virgin Valley, not sure if any more has been found or not yet. I am under the belief that it is the same mineral/opal belt that extends all the way into the blue opal areas in Oregon as well.


I have a nice specimen of very similar blue opal, but it's not from Virgin Valley particularly, but from somewhere in central Nevada. I'll have to dig it out for some pictures and to see my notes on where it came from. I remember that the matrix rock is hard, and it has to be blasted out and much of the material is cracked. My specimen even has some multi-color color-play.

Swish, where did you find syour Psilomelane rough?! I saw it in LJA magazine a while back and think it would be a great stone to set in a piece that has Mokume Gane in it.

Author:  Swishman [ Fri Dec 10, 2010 7:10 pm ]
Post subject:  Re: Select Stones, Cabochon Special Edition

Love the "aboriginal" opal Rom!!!

I forget where I got the Psilomelane rough from honestly, it was eons ago. I really think I got it on Ebay, rofl, back when it was a decent source many many moons ago.

Author:  skycritter [ Sat Dec 11, 2010 9:55 am ]
Post subject:  Re: Select Stones, Cabochon Special Edition

Hey Stonebender-

Here are two sources for psilomelane rough:

http://www.rasrocks.com

http://www.greatrough.com

Cut some and post the pixs!

Author:  Stonebender [ Sat Dec 11, 2010 5:13 pm ]
Post subject:  Re: Select Stones, Cabochon Special Edition

skycritter wrote:
Hey Stonebender-

Here are two sources for psilomelane rough:

http://www.rasrocks.com

http://www.greatrough.com

Cut some and post the pixs!


Thanks! I'll surely post pictures.

Author:  ROM [ Sat Dec 11, 2010 6:37 pm ]
Post subject:  Re: Select Stones, Cabochon Special Edition

Here are a couple of stones from Mexico's Crown of Silver mine I cut recently. I love this material despite the mess it makes during cutting and the difficulty of slabbing it. The manganese oxide in crypto quartz is amazingly tough and pure hell on diamond blades.
Attachment:
psilo3.JPG
psilo3.JPG [ 18.88 KiB | Viewed 854 times ]


And another:
Attachment:
psilo4d.JPG
psilo4d.JPG [ 24.17 KiB | Viewed 854 times ]

Author:  Stonebender [ Sat Dec 11, 2010 6:48 pm ]
Post subject:  Re: Select Stones, Cabochon Special Edition

:shock: :shock: :shock: :shock:

Wow, I'm so obsessed with patterns and shapes. (you should see all the pieces of wood with amazing grain patterns i've saved from my jobs doing woodwork) I must get some of that stuff. Great stones ROM!

Author:  Jung Kee [ Sat Dec 11, 2010 6:53 pm ]
Post subject:  Re: Select Stones, Cabochon Special Edition

Great stones indeed! So is it silicated psilomelane, or quartz that has been infused with manganese oxides? I've got some psilomelane from Sweden, but they are boring to cut as they just turn out blackish like a slab of graphite.

Author:  ROM [ Sat Dec 11, 2010 7:28 pm ]
Post subject:  Re: Select Stones, Cabochon Special Edition

Jung Kee wrote:
Great stones indeed! So is it silicated psilomelane, or quartz that has been infused with manganese oxides? I've got some psilomelane from Sweden, but they are boring to cut as they just turn out blackish like a slab of graphite.

I meant to mention that JK. Yes, the only really cuttable material I've found is the manganese oxide in chalcedony type from the Crown of Silver mine in Mexico. It's not really psilomelane so some people use the name Crown of Silver instead, but the material was originally mined for its manganese content. The pure mineral psilomelane is what you have and its properties are entirely different. There's a psilomelane source in California too but it's like your Swedish material.

Author:  ROM [ Sat Dec 11, 2010 7:36 pm ]
Post subject:  Re: Select Stones, Cabochon Special Edition

Stonebender wrote:
:shock: :shock: :shock: :shock:

Wow, I'm so obsessed with patterns and shapes. (you should see all the pieces of wood with amazing grain patterns i've saved from my jobs doing woodwork) I must get some of that stuff. Great stones ROM!


Thanks! If you enjoy wood patterns Ryan you might enjoy cutting some of this amazing petrified sycamore wood from Washington State. A friend used to carve little owls from it that were amazingly life-like.
Attachment:
DCab 245.JPG
DCab 245.JPG [ 30.64 KiB | Viewed 845 times ]


Another:
Attachment:
Sycamore   Wood - Sold.JPG
Sycamore Wood - Sold.JPG [ 35.77 KiB | Viewed 845 times ]

Author:  Stonebender [ Sat Dec 11, 2010 7:47 pm ]
Post subject:  Re: Select Stones, Cabochon Special Edition

:shock:

You're killin' me here man... :)

Author:  mehoose [ Sat Dec 11, 2010 8:18 pm ]
Post subject:  Re: Select Stones, Cabochon Special Edition

:P Now they are gorgeous ROM =D>

Author:  Doug Frey [ Sun Dec 12, 2010 11:34 am ]
Post subject:  Re: Select Stones, Cabochon Special Edition

Fantastic thread, I am really enjoying all the different cabs. You obviously have an eye for the best material Rick. Interesting to see that some material like the Bruneau agate takes a fantastic polish compared to some of the other cabs shown.
Doug Frey

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