rallyrocks
fully equipped rock polisher
Member since November 2005
Posts: 1,507
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Post by rallyrocks on Apr 1, 2009 13:59:47 GMT -5
Then I guess you need to send a chunk my way so I cab slab it up for you!
I'll only charge 1 slab for every 6 I cut, and I'll pay the return postage ...what do you say?
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Post by akansan on Apr 1, 2009 14:57:10 GMT -5
LOL, Rally. I thought I'd offer as well.
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Post by Michael John on Apr 1, 2009 21:05:28 GMT -5
Welllll ... the "problem", as I see it, is that the whole chunk isn't gonna produce great cabs. The only slabs that will probably have the pretty orbs is the first outer layer, right below the botryoidal formations. If my thinking is correct, then the botryoidal stuff would have to be cut-off first, then a slab would be cut from the "new" outer layer. You'd do this all around the chunk. The "middle" that's left once those outer slabs have been cut would probably be bland and relatively worthless. IF this logical assumption is correct, then the process will be pretty tedious and time-consuming, and a flat-rater full of rough would yield a relatively miniscule amount of slabs.
John ... you still around here? Is that the basic cutting procees?
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Post by akansan on Apr 4, 2009 21:08:16 GMT -5
Hey MJ - I was looking at greatrough.com's psilomene, and they show patterns throughout. In fact, they don't show the botryoidal look at all...
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Post by Michael John on Apr 5, 2009 15:49:15 GMT -5
I just looked at the psilomelane rough at greatrough.com ... $16 - $35 a pound! What's cool is that I've now seen what the actual lapidary-grade rough looks like when it's broken-up a bit. I'm gonna go outside and crack open a piece or two to see how it looks. I'll let ya know.
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Post by Michael John on Apr 5, 2009 18:13:04 GMT -5
Okay, I "busted-up" a couple of pieces and had a closer look at the others...
The grey banding found in SOME psilomelane is pyrolusite. I didn't see any pyrolusite in these samples. However, there's a fair amount of red/orange/yellow barite interspersed, which sometimes looks kinda like moss agate on a black background, and also produces other pretty effects. There are also several distinctly different types of crystals that occur on/in the material (druzy pockets).
Most of the material has obviously been "agatized" ... from my perspective and experience, similar to how chrysocolla mixes with quartz.
In my opinion, and based on my very humble experience, I'd say that this material would make very pretty cabs, and the material does seem very workable. Unlike some other psilomelane, this material won't have grey banding, because I saw no signs of pyrolusite, but the interspersed red/orange/yellow barite provides a very pretty alternative ... some may prefer it, some may not.
Since I'm now pretty confident that this has lapidary possibilities, and since several people have expressed interest, both in this thread and in PMs, I'm going to put together a few of the small flat-rater boxes and list them in the Buy/Sell/Trade section at a very reasonable price, so that people who are interested can get their hands on it. We'll just see where it goes from there.
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rallyrocks
fully equipped rock polisher
Member since November 2005
Posts: 1,507
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Post by rallyrocks on Apr 21, 2009 21:16:16 GMT -5
I took a piece and measured the SG found it to be over 5g/cc (psilomelane is 4.6) and when scratched on the inside of a toilet lid (I don't have a white unglazed piece of tile) it leaves an orange streak (psilomelane would be black). So I'd call this hematite, although its really nice botryoidal hematite. It does makes for a nice little mirror with just a little time on the flat lap;
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Post by johnjsgems on Apr 22, 2009 8:59:53 GMT -5
Natural hematite is pretty rare. Almost all the hematite beads/jewelry and magnetic beads on the market is "hemalike" or some other synthetic form. As an iron it is easily produced in China. Barite won't be of any lapidary use unless it is an agate replacement. Some of the agate pseudomorphs after barite from Utah are amazing.
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