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Post by holajonathan on Oct 20, 2021 11:55:12 GMT -5
Some so-called picture jaspers take a good polish, and others do not. There are so many different names given to picture jaspers, many of which come from the NW United States (especially the Owyhee area).
Some are very hard, high silica rocks, and others are soft, lower silica, muddy, and only polish to a matte finish. I can usually distinguish between the two when I have them in hand, but it is much more difficult based on internet photos of rough rock.
Can someone please name types of picture jasper that take a high polish? Or, conversely, types that do not?
Thank you!
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Post by holajonathan on Oct 20, 2021 22:40:42 GMT -5
I'll add the little I know. Feel free to quote/reply and add to the lists.
Does not polish well:
1. African queen picture "jasper" (sandstone?) from Namibia
2. Disaster Peak "jasper" (rhyolite)
Polishes well
1. Biggs jasper
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Post by rockjunquie on Oct 21, 2021 17:47:41 GMT -5
Deschutes polishes nicely.
I can't identify most picture stones. I just try to get a nice preform and see what kind of polish I get. I got a box from roy that I am just now cutting into. I did one today that has a mirror polish on the 8k wheel. Tomorrow, I'll finish it up. But, I can't tell you what it is. Some of the sandy textured stones are obvious that you can't polish them. But then, some of those matte polishes look good- esp on a nice picture stone. |
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Post by Rockindad on Oct 21, 2021 18:24:00 GMT -5
Probably not exactly what you are looking for but we have been tumbling a few different types recently that have been hitting the polish stage. Some of these pieces will have an incredible shine on one or two "sides" while the rest will get a matte finish. I told A.J. it reminded me of some woods- the difference between the face and end grain, can feel the difference in your fingers. Neat and maddening at the same time.
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Post by jasoninsd on Oct 21, 2021 21:10:52 GMT -5
I know Craig's Gulch Owyhee polishes very well...at least the stuff I have does.
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dshanpnw
fully equipped rock polisher
Member since December 2020
Posts: 1,149
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Post by dshanpnw on Oct 29, 2021 9:48:31 GMT -5
This is a very good question. I know from pics on sellers' stores that Biggs, Owyhee, Wild Horse, and Cripple Creek all shine very well. Then there is what is being called "picture rock" that is rhyolite not jasper. I'm not sure it will shine because it is grainier.
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gemfeller
Cave Dweller 
Member since June 2011
Posts: 4,047 
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Post by gemfeller on Oct 29, 2021 12:40:34 GMT -5
I guess it depends on how you define "picture jasper." Or "jasper" for that matter. Most of the "landscape"-types from the Owyhee region as well as those from the Dead Camel Mountains in Nevada are highly silicified and take good polishes. I make a distinction between them and the so-called "porcelain jaspers" like Morrisonite, Bruneau, Willow Creek, Carrasite, Blue Mountain (am I missing any?) that take amazing polishes due to their great hardness and high silica content.
A few of the "landscapes" I've cut, especially from the McDermitt, NV area, take so-so polishes. Wonderstone, also a landscape type, is basically sandstone and lacks enough silica binding to present a real polish. I think this is a subject that can wander off in several directions due to nomenclature issues. But the comments above are based on my personal experience and understanding of "picture jaspers" in general.
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Post by stardiamond on Oct 29, 2021 19:01:44 GMT -5
Even under the same name, each takes a shine differently. There is a pretty decent definition of a picture jasper. Porcelain jasper doesn't have one.
I have my own which includes Willow Creek, Morrisonite, Carrasite, Imperial, Royal Imperial, Owyhee, Exotica, Bruneau and whatever I forgot. Porcelain jasper, sci-fi and Exotica are also synonymns.
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realrockhound
Cave Dweller
Chucking leaverite at tweekers
Member since June 2020
Posts: 4,459
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Post by realrockhound on Oct 30, 2021 3:04:55 GMT -5
Batcave Jasper from rim of ochoco reservoir. Takes the best shine of all material
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