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What is it?
Untreated Imperial Topaz. 0%  0%  [ 0 ]
Irradiated "Imperial Topaz". 0%  0%  [ 0 ]
Untreated Brown Topaz. 33%  33%  [ 1 ]
Citrine. 0%  0%  [ 0 ]
Quartz. 0%  0%  [ 0 ]
None of the above. 0%  0%  [ 0 ]
Insufficient data to offer opinion. 67%  67%  [ 2 ]
Total votes : 3
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 Post subject: Ordered a monster. Now what is it?
PostPosted: Sun Nov 28, 2021 1:47 am 
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Imperial topaz? Brown topaz? Irradiated? Citrine? Smokey Quartz? What's the catch?

I bought it under the presumption it was a champagne, bordering peach or orange-ish imperial topaz with no treatment. Good seller I've bought from in the past. Said it's untreated and with most of their other stones they're pretty forward about which stones are and are not treated.

That said, I was browsing the gemology online forums and a few gem subreddits which made me question the likelihood of it being irradiated. London Blue topaz is commonly irradiated, but so can the warmer "imperial" shades. And they'll fade to clear when exposed to sunlight.

Also, a good portion of the stone, I'd say about 40% or more of the inside looks crystal clear with almost no color. Photos and even video do it too much justice by adding orange hues.

I tried to upload a video of me turning the stone from various angles but it was taking too long. I'd be happy to figure out how upload a 10-15 second video if that would help with the stone's identification.

Ultimately, I'm trying to understand the value of the stone in its raw or cut/carved form. Any ideas on that would be appreciated as well but that might be more of an appraiser question.


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 Post subject: Re: Ordered a monster. Now what is it?
PostPosted: Mon Nov 29, 2021 6:14 pm 
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Well, to get the first bit out of the way it isn't an imperial topaz. Imperial topaz is distinct from other warm-colored topazes in that it contains chromium which is necessary for the pure red/pink/purple/orange tones that define the variety. You can get brown-pink, brown-orange and brown-red without chromium, but these stones are almost never photostable (with, as far as I know, the sole hard confirmed exceptions being a subset of the 'guererro' topazes from Mexico having stable color). You can also get blue and pure yellow which do not fade.

How can I tell this stone isn't imperial just by looking? Two main reasons:

First, Imperial topaz has a distinctive crystal form--it (as far as we've ever found, so far, in existing deposits) only occurs in metamorphic rocks, and grows with a distinctive prismatic crystal habit. Brazil is the main source, though minor deposits exist in Pakistan, Russia and Zambia.

Second: large topaz crystals pretty much only occur in igneous pegmatites. This is the most common type of topaz deposit, with many of them all over the world producing a fair quantity of topaz. Igneous pegmatites don't tend to be rich in chromium for geochemical reasons, and as far as we've ever found chromium-bearing topaz just doesn't occur in them.

Both non-imperial and imperial topaz can be irradiated to deepen the color. Non-chromian topaz can go a variety of shades of brownish red, brownish pink, brownish brown, which will fade with exposure to sunlight (again, as far as I firmly know only with the exception of some Mexican stones). The browns can fade very quickly or slowly in sunlight, and don't fade in the dark. Irradiating chromium-bearing topaz in contrast tends to produce turbocharged red and red-orange colors, which unfortunately fade quickly in sunlight, either to a lighter peach, to colorless or even to pink. What controls the level of stability isn't exactly known.

OK, let's get back to your particular stone. For a video I'd recommend uploading it to youtube and embedding the video here.
My visual impression from the photos (and it is just that, an impression) is that it appears to have a hexagonalish outline--topaz can be pseudohexagonal but this doesn't look like that to me--to me it looks more like a weathered quartz crystal. The color (to the extent it's possible to tell, which isn't much) doesn't look topazy to me either--more smoky than brown (again, resembling a quartzy color range more than topaz). I also don't see any flat cleavage faces, which will definitely be present on a broken stone like this if it is topaz. My bet is on quartz. You can test this in a few ways--first, look for those cleavage faces. Topaz breaks perfectly flat in one direction, and the flat polished faces will flash as they catch the light. A video will have a better chance of showing off this particular feature than still photos. If you don't see anything like that it is almost certainly not topaz. You can also measure the specific gravity if you have a carat scale--it is not very difficult and gives a great piece of information to at least exclude some possibly identities.

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 Post subject: Re: Ordered a monster. Now what is it?
PostPosted: Mon Nov 29, 2021 9:09 pm 
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I kind of have to agree with Stephen, my first thought was quartz. It is quite large, you are going to need a pretty good size setup for getting an sg reading. Looks like it has quite a bit of iron staining. The two pics are very blurry hard to see anything to detailed.

Stephen in the scale pic at the top right corner of the stone, do you see the porosity area. Does that indicate anything to you. I have agate material that has this especially in my limb cast material.
I do not believe to be topaz either. Definitely not any imperial topaz.

Why are we voting? The vote isn't going to Id it.

Without a true identification it is hard to put a value on it. Topaz and quartz are not all that valuable, my best thought for you would be hope it is identified as morganite that would get you a somewhat better value. I do not think your supplier would have let it go if that were a chance though.

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 Post subject: Re: Ordered a monster. Now what is it?
PostPosted: Tue Nov 30, 2021 6:50 am 
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Maybe Calcite ...

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 Post subject: Re: Ordered a monster. Now what is it?
PostPosted: Tue Nov 30, 2021 11:35 am 
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The stone has many broken and eroded surfaces judging from the limited views in the images. I see no shinny flat surfaces on and if the broken areas. No cleavage means no Topaz.

It would never be called "Imperial" Topaz in any case. It would be called "Precious" Topaz.

Judging by the tint on the white background areas it looks like the white balance in the image is off making the color in the stone not reliable either.

I am with Stephen on this. Most likely Quartz. But many other possibilities as well. Second guess would be Beryl. Should be an easy determination with even a minimum set of tools.


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 Post subject: Re: Ordered a monster. Now what is it?
PostPosted: Tue Nov 30, 2021 7:41 pm 
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Here are the links to the videos I tried to upload earlier:
1. 36 Seconds - https://vimeo.com/651428068
2. 6 Seconds - https://vimeo.com/651429589
3. 7 Seconds - https://vimeo.com/651430017
Stephen Challener wrote:
Both non-imperial and imperial topaz can be irradiated to deepen the color. Non-chromian topaz can go a variety of shades of brownish red, brownish pink, brownish brown...

There's this video on YouTube titled 'Topaz Stone Irradiated in RSG-GAS reactor (Indonesia)'. In it there's a before image of what is supposed to be a large white topaz before being irradiated to a dark blue color. Timestamped link: https://youtu.be/eNL59hT0RvI?t=12
If that is topaz in the above video, the shape and size of it remind me of this rough I bought as well as some of the other portions this seller was selling. The seller had another piece with a bit more 'fire', at least in photos, that was purchased a few months ago and was re-listed with the new seller marking up the price. The new seller had a photo of a presidium gem tester over the specimen where the meter registered as 'Topaz' (I don't know how reliable these are though).
Stephen Challener wrote:
My visual impression from the photos (and it is just that, an impression) is that it appears to have a hexagonalish outline--topaz can be pseudohexagonal but this doesn't look like that to me--to me it looks more like a weathered quartz crystal. The color (to the extent it's possible to tell, which isn't much) doesn't look topazy to me either--more smoky than brown (again, resembling a quartzy color range more than topaz). I also don't see any flat cleavage faces, which will definitely be present on a broken stone like this if it is topaz. My bet is on quartz. You can test this in a few ways--first, look for those cleavage faces. Topaz breaks perfectly flat in one direction, and the flat polished faces will flash as they catch the light. A video will have a better chance of showing off this particular feature than still photos. If you don't see anything like that it is almost certainly not topaz.

I see what you're saying. Examples of Imperial Topaz I've seen have that crystalline, hexagon-ish shape with more of a pink/red/orange hue throughout the piece from the chromium. The color I'm really confused about because the inside looks more like more of a clear/champagne compared to the outside which is browner or smokier.
I think one of the shorter sides looks like it has a flat cleavage plane around the outside (the texture is a little bumpy, not smooth). Then there's a smaller, maybe 1cm plane connected to another side has kind of an inward "v" shape or like the roof of a house with two flat planes. The other two sides look mostly bumpy to me with the exception of a few smooth, clear windows into the crystal. The small, clear windows seem to flash on camera.
I guess the question I have is, could a topaz crystal be weathered like this or is that unlikely? I see your impression, though, it doesn't look like any of the other 'imperial topaz' I've seen.
Stephen Challener wrote:
You can also measure the specific gravity if you have a carat scale--it is not very difficult and gives a great piece of information to at least exclude some possibly identities.

I have a pocket carat scale but the piece was too large for it and it didn't register. I could use the gram scale though if that'd provide an accurate enough reading. I will look up how to do that soon (obviously I'm an untrained novice).
I've attached a photo with more information about the origination and purchase, including photos of other types of rough the seller has sold like citrine and smokey quartz. Hope this answers more questions than it raises.


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 Post subject: Re: Ordered a monster. Now what is it?
PostPosted: Tue Nov 30, 2021 7:57 pm 
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Tried to upload this earlier. Covers where the stone was sourced as well as some other rough came from, including other 'topaz' in question from the same parcel, citrine, smokey quartz, etc. Hope it answers more questions than it raises.


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 Post subject: Re: Ordered a monster. Now what is it?
PostPosted: Wed Dec 01, 2021 12:26 am 
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I have dealt with this buyer some years ago on some natural unheated neon apatite, relatively good sizes for apatite. Only going to say not what they were claimed and were direct shipped from Thailand. When requested a return they stated I would have to send back to Thailand. That didn't work out well for them. Prior to that I purchased from this seller a large said to be Syberian Amethst, I knew that was pretty much not likely but pictures made it appear deeply saturated with some reddish undertones, unfortunately it arrived and after I removed the heavy oiling it wasn't as dark as it appeared, it was still a nice piece of rough just not what all fluffing it was given on ebay. These pics to me say oiled. It's always buyer beware on eBay but if you understand that going in you can make sensible decisions. In your case with no gemological experience or anyone with any your going to have be a bit cautious.
This seller back some time ago was dealing mostly quartz and very little other gems.

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 Post subject: Re: Ordered a monster. Now what is it?
PostPosted: Wed Dec 01, 2021 12:39 pm 
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Okay, so I took a few different readings of specific gravity. I'm not sure how precise it is for differentiating different types of topaz.

The mass measurement from two days ago was 616g. I re-measured today at 615g. The water displacement reading (density) was most constant at 174g, second-most at 175g (hovering from 173g to 176g on the scale).

So the specific gravity, I believe is 615g / 174cu^3 = 3.53

From a quick google it looks like topaz falls from 3.49 - 3.57, so it's topaz.

I'm not super confident what type of topaz it is here as I'm second-guessing which readings were best to use but generally the range is from 3.51-3.54 using the numbers given.

I agree with glhays in that the photos were oiled. I previously ordered some peridot from them which had some white dust around the outside (or maybe they got it wet before the photo). They're usually at least somewhat disclosing about treatments on their stones, some say 'color enhanced', 'clarity enhanced', 'hardness enhanced'... nothing stated on the Topaz though except for 'no treatment' which I've was more suspicious of if it was imperial/precious topaz. Either way, I was prepared for this kind of thing. I think the natural pink-orange-red hue being missing drops the value from potentially $1000-$2500 per carat to less than $8 per carat after being cut so no early retirement for me. Wah. It cost ~$0.22 per carat all said and done, which is okay. I might keep it if it's unusual enough for common Topaz to be 3000ct and above.


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 Post subject: Re: Ordered a monster. Now what is it?
PostPosted: Wed Dec 01, 2021 1:15 pm 
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I am also familiar with this seller, though what I got was fairly good (though poorly labeled, hence being able to get a deal).

The videos give a much better idea, as well as the SG of course--a classic example of how impressions from photos can be misleading. I still don't clearly see any cleavage planes but I bet they're there. It has the sort of classic partially et hed skin I'd expect on a topaz chunk like this, and more importantly the sharp zones of dark brown which are a typical sight in irradiated topazes. That's a big 'ol pegmatitic topaz, definitely not imperial but real topaz. I would guess its color is from irradiation, though I couldn't prove it. Regrettably it looks like the color is concentrated in that outer zone, so even if it were stable you'd never see it in a finished stone unless you just cut a portion of the rind. You'd probably get an effectively colorless stone. Still, it's a neat piece.

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 Post subject: Re: Ordered a monster. Now what is it?
PostPosted: Wed Dec 01, 2021 3:20 pm 
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Topaz as a retirement investment, that is a well established bad retirement future.
Near color-less material makes for good color enhancement (Mystic Topaz, and many other exotic names out there). It is quite abundant out in the markets, low cost and used to be used a lot as accent stones in jewelry replacing the lower RI quartz.
Getting even 8$ p/CT for cut stones is a hard sell, trade experienced can purchase the blues (Swiss, Electric, London) for far less than that. Usually $1.50 to $2.75 p/CT in parcel lot quantities.
Happy to hear you got what you purchased.

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