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 Post subject: Re: A little help, please?
PostPosted: Wed Oct 17, 2012 9:50 am 
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The red usually fades first (Or perhaps the red fade is more dramatic). In extreme cases the stone will fade to nearly water white.)
The car window filters most UV, so compared to open sunlight is is very gentle and slow.
usually if topaz does not fade in a week in OPEN SUN, it is not going to. Sometimes they fade a little, and reach what seems to be a stable end point.


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 Post subject: Re: A little help, please?
PostPosted: Thu Oct 18, 2012 4:36 am 
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Okay, that's what I was thinking, you answered my next question: if it doesn't fade to clear, is there a stable medium that it goes to.

Another question (not specifically related to this rough, but using a picture of it), when using a camera's flash on a rough, what would cause a certain color to propagate the stone?


I took this image with the camera's flash turned on and was wondering: is it the amount of photons being pumped into the rough that is causing the color to be so vibrant, or is there something else that I'm missing?

As far as fade testing, recommendations for a means to open exposure for the rough? I don't really have a good place to put it as I live in an apartment complex. Would my best bet be to purchase a wide spectrum light? If so, what are some recommendations, since I'm not exactly experienced in this area...?


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 Post subject: Re: A little help, please?
PostPosted: Thu Oct 18, 2012 7:40 am 
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Quote:
I took this image with the camera's flash turned on and was wondering: is it the amount of photons being pumped into the rough that is causing the color to be so vibrant, or is there something else that I'm missing?


Prbably just scattering the C Axis Red.

Quote:
As far as fade testing, recommendations for a means to open exposure for the rough? I don't really have a good place to put it as I live in an apartment complex. Would my best bet be to purchase a wide spectrum light? If so, what are some recommendations, since I'm not exactly experienced in this area...?


You need UV for a real test. Use a tanning lamp. You can get the old ones on EBay cheap.

Image

These contain a quartz mercury vapor internal lamp. PROTECT EYES. 254 nm UV. Do not stare at lamp. Put it in another room and let it run an hour. I did a post on here some time ago about forced UV Fading on Gurerro topaz, but cannot locate it. I used a quartz germicidal lamp. They can be dangerous though.


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 Post subject: Re: A little help, please?
PostPosted: Thu Oct 18, 2012 9:48 am 
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Try an aquarium light. Broad spectrum and little heat. In my most recent topaz excapade one efficiently reduced (alas!) A few 'fine' topaz to beige in about a day. It apparently gives a wide enough range to effectively simulate sunlight.

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 Post subject: Re: A little help, please?
PostPosted: Fri Oct 19, 2012 6:21 pm 
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I'm thinking that I'll just get it cut regardless. I like the way it looks now, if I protect it from light like you would Kunzite it should be fine, in theory, at least.

The biggest thing I'm noticing with this is color memory is unreliable. I've been taking photographs of progression and it almost appears as though the color fluctuates, sometimes darker sometimes lighter, likely due to my inexperience with lighting and controlling associated conditions. The red mightn't be as strong, but it's still there, it's also very clean.

Here's the final set of pictures, in sunlight, before sending it off:
Showing off the color banding:
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(Click to enlarge)





Is this a bad decision, or can any light affect the color?


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 Post subject: Re: A little help, please?
PostPosted: Fri Dec 07, 2012 7:35 pm 
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Sent it to the Lapidary, estimates about 16mm Trillion Cut (the shape is a personal choice.) I'm going with the axis which yields an orange-ish hue. Here's hoping it looks decent when cut. I know all the chances related to color fading, but I figure if I'm keeping it, who cares?

Now what to do about the mount...

I'm thinking a pendant, but I'm not entirely sure. It's too big to work for a ring (at least anything my lady would wear, that is.)


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 Post subject: Re: A little help, please?
PostPosted: Sat Dec 08, 2012 5:01 pm 
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You never know. I had a small parcel of vivid, mandariny-orange (alas, thoroughly irradiated) katlang stuff which I've left in the sun. Most of it faded to pale golden, a couple to faint pink, but one of them has kept its orange hue despite a few day's worth of sun. I also have one that I had cut when it was vivid orange, which has faded but stabilized at a rather attractive golden color. So you may still get something from the deal, aside from the fun of the process.
A pendant sounds like a good choice to me, but it's probably a good idea to wait to see what it looks like.

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 Post subject: Re: A little help, please?
PostPosted: Sat Dec 08, 2012 11:53 pm 
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Also, lapidaries are expensive. I'm surpriseed a 16mm stone would cost $400+ to cut.

Guess this is part of the learning experience?


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 Post subject: Re: A little help, please?
PostPosted: Sun Dec 09, 2012 7:20 am 
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Also, lapidaries are expensive. I'm surpriseed a 16mm stone would cost $400+ to cut.

It depends on if you said, "Cut it and make it sparkly", or if you pulled out a gemcad design and said, "I want this specific cut", and who the cutter is.


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 Post subject: Re: A little help, please?
PostPosted: Sun Dec 09, 2012 10:51 am 
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I asked for the best trillion cut possible based upon the orientation. Which meant I have to rely on his expertise. I could've suggested something else; however, the cost would've been more than doubled (I asked, the shape wasn't that important to me, according to my pocket book.)


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