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PostPosted: Fri Sep 18, 2009 1:59 pm 
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I have some rather bright (slightly brownish) orange rough that was sold to me as grossular. It looks rather like spessartite at first glance. I haven't tested it to confirm, but Steve usually knows what he's selling.

Image

I took the photo with my iPhone, so I had to monkey with the colors to get them right... but on my monitor, this closely replicates how it looks to the eye. The stones total ~22 carats.


Last edited by gem-n00b on Fri Sep 18, 2009 2:01 pm, edited 2 times in total.

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PostPosted: Fri Sep 18, 2009 2:00 pm 
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Pedro, do you mean translating? Traducing has a different meaning in English...


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PostPosted: Fri Sep 18, 2009 2:41 pm 
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gem-n00b wrote:
I have some rather bright (slightly brownish) orange rough that was sold to me as grossular.


Was this part of the imperial topaz thread?

That is some weird looking grossular (just looking at the color in the photo, of course).


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PostPosted: Fri Sep 18, 2009 2:42 pm 
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I have some peach-colored grossular crystals from Canada, a bit like that.


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PostPosted: Fri Sep 18, 2009 3:11 pm 
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Oops! Sorry! I missed all those comments about the garnets on p. 7.


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PostPosted: Fri Sep 18, 2009 3:32 pm 
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Here I am, having to take back something.

I am looking right now of a photo of a gorgeous salmon-colored topaz crystal from Ghundao Hill, Pakistan (about 20 mm in length).

It is in the book "The Complete Encyclopedia of Minerals" by Petr Korbel and Milan Novák, Chartwell Books, 1999, p. 202. ISBN 0-7858-1520-1.

I don't know if it shimmers, but it looks like it might.


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 Post subject: Imperial Topaz
PostPosted: Fri Sep 18, 2009 7:02 pm 
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At the mines, the few serious dealers that differenciate use a redish c-axis as the guide. If there is no pink, red, purple in the stone, they don't consider it Imperial. Color is the only determining factor there.

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 Post subject: Re: Imperial Topaz
PostPosted: Fri Sep 18, 2009 7:17 pm 
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David Epstein wrote:
At the mines, the few serious dealers that differenciate use a redish c-axis as the guide. If there is no pink, red, purple in the stone, they don't consider it Imperial. Color is the only determining factor there.


Common topaz will not have those colors -- by common, I mean the larger crystals that have no shimmer, and also do not have the very fine fissures.

mindat.org calls imperial topaz a variety of topaz (not that I know what they mean exactly by "variety"), and they have a nice gallery of photos of imperial topaz crystals. You can see gross examples of the fissures.

http://www.mindat.org/min-8110.html

Better colors have imperial prices, that is for sure.


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PostPosted: Sat Sep 19, 2009 6:59 am 
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I would just like to add some additional information concerning the crystals of imperial topaz as shown on mindat.

That site currently has over 50 photos of imperial topaz crystals of the various natural colors. The first, a light golden brandy in color, displays the typical size, shape, color, and form of the most commonly found imperial topaz crystal, not to mention the internal fractures. These crystals can be had for pennies, as they are not gem quality and are sold merely as curiosities. The descriptions of the imperial topaz crystals on mindat contain a lot of hype. Almost none of the brandy-colored crystals is gem quality. The lavender crystals, however, are valuable. Here is the link, again:

http://www.mindat.org/min-8110.html


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PostPosted: Sat Sep 19, 2009 10:33 am 
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yesterday i was looking for imperial topaz but didn´t found much, just red imperial topaz for sale but very bad fotos. the other place is flickr . awsome other gems and rough here. take search it worth´s the time.
gringa duarte&bastos galerie exist in flickr. very nice specimens of brazilian stones, a lot of good mozambique paraíba here to, some brazilian ones to compare. it realy worth take a look everyone


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PostPosted: Tue Sep 22, 2009 4:47 am 
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Heya Folks,

Seeing as how the topic of treated topaz was being discussed I thought I'd share my own experience.

This season there was an elderly fellow out at the gemfields for a while. Someone mentioned that he had some brown topaz so I went over and had a look. A few people beforehand quietly told me their reservations about this fellow and "becareful, his topaz fades".

Anyway, my first impressions were a bit suspicious. He said that he had found this patch of cinnamon brown topaz on the fields back in the 70's when he was pushing a track through to his workings. It was in a gully but he couldn't remember where. (yeah, right!). This got the alarm bells ringing a little and also the fact that he was the only person I knew or heard of that had found this brown topaz. Even people who had lived there for over 40 years said they had never found a single one of these "brown" topaz... you simply don't get them here.

So I bought four off him to give a go and see what would happen. Now I took a "before" photo of the stones and then selected one to go outside in the direct sunlight for 5 days.

I then took an "after" photo.... that stone went completely clear!!! I wasn't surprised.

So chalk that one down for experience and now I know that this fellow is dodgy. Its surprises me that someone would do that out there cause he was always going to get caught out. He's left now but next season if here is there I might have a quiet chat to him about this.

Anyway, here are the pics :

Image
Image

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PostPosted: Tue Sep 22, 2009 7:08 am 
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Pedro wrote:
yesterday i was looking for imperial topaz but didn´t found much, just red imperial topaz for sale but very bad fotos. the other place is flickr . awsome other gems and rough here. take search it worth´s the time.
gringa duarte&bastos galerie exist in flickr. very nice specimens of brazilian stones, a lot of good mozambique paraíba here to, some brazilian ones to compare. it realy worth take a look everyone


Dear Pedro,

Anfilófio Bastos is a good friend of mine, and we are mutual contacts on flickr. He gave me permission to use one of his imperial topaz photos on my blog. I used the long comment I made here, his photo, and some additional text for a blog post.

Photographing imperial topaz is very hard work due to the invariable black reflections on the facets at the bottom of the pavilion. Over the years, he and I have managed to find ways to eliminate most of these reflections, but they still show up on occasion.

Right now, Duarte & Bastos probably has the best quality copper-bearing tourmalines from Mozambique that are available in Teófilo Otoni.

And their imperial topazes are out of this world. Here is a link to Filó's flickr set of imperial topaz -- remember that even though the camera records those black reflections, the brain largely eliminates them when a person views the actual stone in person:

http://www.flickr.com/photos/dbprecious ... 84/detail/


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PostPosted: Tue Sep 22, 2009 9:45 am 
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very very nice :D
love those reds.
i like black flashes on gems, it´s personal taste, look beter in darker gems, in green ones specialy :P
thanks gringa :)


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PostPosted: Tue Sep 22, 2009 4:33 pm 
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:D what is the difference between "imperial" and "precious" topaz?? or are they the same? does unenhanced topaz fade like the irradiated or heated?

doug, i imagine you were not surprised after the topaz faded after being in the sun for 5 days. cannot believe the guy tried to convince you that he had found brown topaz, lol!!


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PostPosted: Tue Sep 22, 2009 4:37 pm 
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gingerkid wrote:
:D what is the difference between "imperial" and "precious" topaz?? or are they the same?


I think this is a very good question. Imperial topaz has unique characteristics, making it a variety of topaz, according to mindat.org

So, what is "precious" topaz? This seems to be a somewhat nebulous term perhaps used to facilitate sales of very good quality topazes of any variety.


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