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Author Topic: Need information about Chrysopal vs. chrysoprase  (Read 2917 times)

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ileney

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Need information about Chrysopal vs. chrysoprase
« on: June 03, 2017, 08:41:12 PM »

I'm a bit confused about this stone, Chrysopal, that I bought recently (left). It looks a bit like pale lime sherbert, a pastel color. I've found very little information about it online other than that it is "transitive to Chrysoprase." I have absolutely no idea what that is supposed to mean. For comparison, I placed a piece of Chrysoprase rough next to it. As you can see, the chrysopal is covered in a very, very, white exterior rind, and that rind feels almost like talc. The chysoprase has a much rougher, darker rind. The chrysoprase is a clearer, darker green, whereas the chryopal gives an effect of being uniformly cloudier in color and paler. Does anyone have information about  this stone? Is it readily available or rare?
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gemfeller

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Re: Need information about Chrysopal vs. chrysoprase
« Reply #1 on: June 03, 2017, 10:20:50 PM »

As far as I can learn the only thing shared between most green chrysopal and chrysoprase is the nickel coloring agent.  One is opal, the other is chalcedony. Others more learned than me may be able to document whether chrysopal transitions to chrysoprase, but from what can learn, chrysoprase can often be silicified magnesite.  The variety called lemon chrysoprase is magnesite, not chrysoprase.  There's an image of chrysoprase with a yellowish blob of magnesite in the center here: http://www.outbackmining.com/chrysoprase-magnesite-core.jpg

I have some chrysopal said to be from Macedonia that's very similar to the mint green piece you posted.  Almost identical material is also coming from Indonesia.  Both have the white rind and both appear to be from vein deposits.  I've also seen chrysopal from Tanzania, I believe.  There may be other sources.  It appears to be somewhat available based on a search of EBay.

I'll shoot an image of my Macedonian opal and post it tomorrow.  I find the color very attractive but it was mined by blasting and the shock resulted in many microfractures.   
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gemfeller

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Re: Need information about Chrysopal vs. chrysoprase
« Reply #2 on: June 04, 2017, 03:13:10 PM »

This is the Macedonian chrysopal image I promised.  This piece weighs about 10 pounds.  I haven't seen much if any of this material on the market since I bought this and a few other pieces in Tucson quite a few years ago now.

DSCN1557 (375x234).jpg
*DSCN1557 (375x234).jpg (82.78 kB . 375x234 - viewed 769 times)
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ileney

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Re: Need information about Chrysopal vs. chrysoprase
« Reply #3 on: June 05, 2017, 12:13:36 PM »

Pretty. My stone is not very large. I believe my stone is from Indonesia. I don't think it was blasted out as the rind seems intact and the material seems pretty solid looking, not many fractures, but I guess I'll find out when I start to cab it.
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raven.worldlrnr

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Re: Need information about Chrysopal vs. chrysoprase
« Reply #4 on: June 29, 2017, 09:55:34 AM »

Pretty. My stone is not very large. I believe my stone is from Indonesia. I don't think it was blasted out as the rind seems intact and the material seems pretty solid looking, not many fractures, but I guess I'll find out when I start to cab it.
Hi, Wondering how its going with the cabbing? I have some smaller stones and wondering how the stone is reacting. I want to put it in mahogany for necklaces

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ileney

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Re: Need information about Chrysopal vs. chrysoprase
« Reply #5 on: June 29, 2017, 12:38:33 PM »

Yours looks a little different from mine. Mine looks more milky now. It may have absorbed water during grinding I suspect. It seems to develop white bruising very easily during sanding stage, with pressure. Also, there are small pockets here and there which make navigating it and geting a completely clean slab difficult. I haven't tried stabilizing it as I am still trying to give it a go and see how it looks if I'm quite gentle with it. I'm trying to slab rather than grind it initially since it bruises so easily. It's still a pretty color and has a soft feel to it.
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raven.worldlrnr

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Re: Need information about Chrysopal vs. chrysoprase
« Reply #6 on: June 29, 2017, 01:44:21 PM »

Thanks for the info its sure pretty.

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ileney

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This is an update because I realized I never posted what happened with this Indonesian "chrysopal" material. I have seen others selling it now, but none are warning about what to do to cab it succesfully.  This stuff reminds me of Ethiopian opal in that I think it is hydrophane and has the problems associated with hydrophane stones. The cabs turned an unpleasant brownish yellowish-green color, I think because they absorbed the dirty water in the bottom of the tray. The original color was very beautiful, so that was disappointing. They also never had a hard shine. I have a bigger chunk which I never cut and it still looks fine. I think I will try stabilizing it before I cab it. I may slice off a piece at some point and try either epoxy or opticon and see if that works before doing the rest of the stone. Anyone have experience cabbing this stuff?
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jmb1974

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Re: Need information about Chrysopal vs. chrysoprase
« Reply #8 on: July 29, 2020, 05:12:44 AM »

Did you ever find a way to keep the color while cabbing?  I have a large chunk of this and was thinking of cutting it. Thanks
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Felicia

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Re: Need information about Chrysopal vs. chrysoprase
« Reply #9 on: July 29, 2020, 12:30:22 PM »

This is interesting, I've never worked with chrysopal and know very little about it. The first time I worked with Ethiopian opal, found some at a show, didn't know it was a hydrophane. Surprise as I started to sand it! Set it aside for a couple of days, it came back. Then looked it up. Use distilled water on it now. The stone you have has some really nice color, hope you find a good way to use it. Should make lovely jewelry!
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Stonemon

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Re: Need information about Chrysopal vs. chrysoprase
« Reply #10 on: July 29, 2020, 03:14:55 PM »

Did you ever find a way to keep the color while cabbing?  I have a large chunk of this and was thinking of cutting it. Thanks

Welcome to the forum!
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Bill

ileney

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Re: Need information about Chrysopal vs. chrysoprase
« Reply #11 on: August 03, 2020, 03:18:10 PM »

No. Since it turned colors, I've been reluctant to slab the other stone as it is so pretty before cabbing. However, I noticed on etsy that someone was selling some cabs and they were still the pretty aqua green color, though still not so glowy as before, so either their material was more stable or they figured out some way to stop it from turning muddy.
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lithicbeads

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Re: Need information about Chrysopal vs. chrysoprase
« Reply #12 on: August 03, 2020, 03:48:04 PM »

Over 40 years ago this mix was coming out of Africa and now out of Indonesia. The African mix was much more green and cut better. I cut some of the Indonesian rough about 10 years ago and won't do it again. After cutting opal for decades and having stones craze and be returned 20 years after cutting them it makes more sense to buy stable well silicified rough . Very beautiful and very problematic.
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