I recently acquired these two pieces. The first was sold as "smoky quartz". I have other pieces of SQ and they're not nearly as dark, so I was intrigued by its appearance. I since did some research and it looks like the reason it's so dark is because it was likely irradiated.
This second piece was sold as "smoky amethyst". I was suspicious that it was tampered with. I asked the person selling it. He told me that he recently acquired it and it was from a cave that was very hot and it's why the tips turned so dark. My spidey senses tingled, but I thought that if it was natural, it was a very beautiful specimen. My research to try to verify if it's natural has come with nothing.
Smoky quartz can naturally come that dark (from exposure to natural radiation) or be irradiated to that color artificially. No way to be sure. The other one does look suspicious. There are a lot of chinese-made specimens with a light overgrowth of sybthetic quartz over a natural cluster, including yellow and purple overgrowths. We'd need some clearer photos without the watermarks to get a good look. The hot cave story is definitely BS though.
Smoky quartz can naturally come that dark (from exposure to natural radiation) or be irradiated to that color artificially. No way to be sure. The other one does look suspicious. There are a lot of chinese-made specimens with a light overgrowth of sybthetic quartz over a natural cluster, including yellow and purple overgrowths. We'd need some clearer photos without the watermarks to get a good look. The hot cave story is definitely BS though.
Thanks for the reply, Stephen. Your description of these Chinese specimens sounds like it could be what I have: light overgrowth of quartz over a cluster.
That's the stuff! Here's a picture of one with an edge broken off that someone was showing off at Tucson this year:
(As a side-note, your post temporarily disappeared because you have under 10 posts, so each post still has to be approved. This applies to edits as well which require reapproval, an unfortunate necessity.)
There can certainly be natural overgrowths of later quartz over quartz at times. A classic example is 'cactucs quartz' with fine druze over a larger single crystal. But not like these.
Joined: Sun Oct 16, 2005 12:22 pm Posts: 21602 Location: San Francisco
I have a very large specimen of quartz xls which have been covered with a drusy coating. White though, nothing as dramatic as your specimen, gimmethosecrystals.
The person I bought this from is arguing that the story is BS and I don't really know how to discuss this with him.
Would you mind explaining why it's BS? Obviously, temperature can have an effect (e.g. heat-treated amethyst --> "citrine"). My background is psychology not gemology. I'm just a rock lover and am here to learn.
Quartz crystals are not typically recovered from caves, for one. Heat can change quartz's color but higher temperatures than are found in caves. Heat in particular also does not improve amethyst's or smoky quartz's color, which is bleached or turns yellow by heat. Radiation would be required to bump up amethyst's or smoky quartz's color. It is a load of nonsense end to end.
Quartz crystals are not typically recovered from caves, for one. Heat can change quartz's color but higher temperatures than are found in caves. Heat in particular also does not improve amethyst's or smoky quartz's color, which is bleached or turns yellow by heat. Radiation would be required to bump up amethyst's or smoky quartz's color. It is a load of nonsense end to end.
Stephen and Barbra - thank so much for the information. I appreciate your knowledge and help!
The guy is saying he's going to get a second opinion form a certified gemologist. Let's see what he comes back with.
Just as a side-note, this isn't really something that most gemological curricula would touch on. These are known fakes in the trade (more typically seen with a layer of green chromium salts between the natural quartz and the synthetic to add a phantom effect) but will never cross most gemologists' desks because they're in a different market.
Just as a side-note, this isn't really something that most gemological curricula would touch on. These are known fakes in the trade (more typically seen with a layer of green chromium salts between the natural quartz and the synthetic to add a phantom effect) but will never cross most gemologists' desks because they're in a different market.
I have a lot to learn. I thought gemologists would be able to ascertain something like this. I guess it also means you're not a gemologist.
Please, correct my error. If you're not a gemologist, what are you?
I'm in the difficult position of this not being my area of expertise yet knowing this piece isn't authentic and trying to negotiate that. I at least want all the facts I can get -- including the experience or credentials of the people I'm speaking with.
There are many people here that have World Class credentials.
Stephen is a degreed geologist, with years of experience in stones and minerals.
Barbra is both a geologist and a graduate gemologist as am I.
The problem is not the credentials, or knowledge of those trying to help you. It is just that with all opinions based on looking at a picture on line, it should be recognized that they are guesses and not the result of actual examination, and testing of the piece in question. To do otherwise would be reckless, and the experts here are too professional to do that.
Gemmology is the study of gem material. This focuses on cut gem material. The pieces in question here are mineral specimens. This is a different specialty although many people do deal in both types of stones. Stephen is one who does this. I think that what Stephen was trying to point out is that taking these items to a "certified gemologists" is probably not who you need to consult with. They likely don't have the expertise required in this area.
There are many people here that have World Class credentials.
Stephen is a degreed geologist, with years of experience in stones and minerals.
Barbara is both a geologist and a graduate gemologist as am I.
The problem is not the credentials, or knowledge of those trying to help you. It is just that with all opinions based on looking at a picture on line, it should be recognized that they are guesses and not the result of actual examination, and testing of the piece in question. To do otherwise would be reckless, and the experts here are too professional to do that.
Gemmology is the study of gem material. This focuses on cut gem material. The pieces in question here are mineral specimens. This is a different specialty although many people do deal in both types of stones. Stephen is one who does this. I think that what Stephen was trying to point out is that taking these items to a "certified gemologists" is probably not who you need to consult with. They likely don't have the expertise required in this area.
I appreciate the information and I'm sorry if the lack of clarity of my words have caused any offense. This isn't about my personal need for credentials but that this guy is refuting this is an artificially-created specimen. He said he's going to get a second opinion from a certified gemologist. And my being able to say, "hey, this is the opinion of some geologists," will give my position more weight than "some people I don't know online". That's all.
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