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 Post subject: Re: Purchased Tsavorites that do not register red Chelsea fi
PostPosted: Mon Nov 12, 2012 1:09 am 
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Thanks for the info. There are so many options, especially with all the cheap Ebay alternatives. This is becoming a very expensive hobby!


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 Post subject: Re: Purchased Tsavorites that do not register red Chelsea fi
PostPosted: Thu Nov 15, 2012 7:04 pm 
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Don't go crazy, it's not only about the equipment, your skills and knowledge are more important, better tools just help. I know some gem dealers in third world countries that identify stones just by looking at them, and are rarely ever mistaken, they just have seen a ton of that stuff and know how it looks feels and smells 8)

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 Post subject: Re: Purchased Tsavorites that do not register red Chelsea fi
PostPosted: Mon Nov 26, 2012 12:07 am 
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Thanks, Kane. I'm limiting my purchases to the OPL spectroscope and dichroscope, a cheap Ebay hand-held polariscope, a good led pen light, a 6$ eBay 60x led-loupe, my original 10x loupe, and an SG kit from Prettyrock.com. I'm planning on buying a cheap Ebay refractometer and going to splurge on the Presidium duo. I'm not going to purchase a microscope for a while since I'm all inclusions seem to look the same to me (doh!). I did manage to ID curved striations in a fake sapphire with my 6$ loupe, which made me extremely happy. I couldn't see the striations with a $65 hand-held dark field loupe so I decided that it was either flawed or I don't know how to use it. The optics seemed questionable since it was fuzzy around the edges, so I returned it (it was supposed to a quality triplet, but my 20 year old 10x loupe from Japan leaves it in the dust).


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 Post subject: Re: Purchased Tsavorites that do not register red Chelsea fi
PostPosted: Mon Nov 26, 2012 1:17 pm 
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Seriously...forget about the Presidium and spend the money on a better refractometer.


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 Post subject: Re: Purchased Tsavorites that do not register red Chelsea fi
PostPosted: Mon Nov 26, 2012 8:38 pm 
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Thanks for the advice, Barbara. I'll consider it. I received my OPL instruments last week from Colin Winter. He is such a great guy. Using my new spectroscope, I looked at a rough Tsavorite I received from Prettyrock.com. To my eyes, it looks like the absorption is at both ends, both in the red and the blue. Could this be right? I'll try and photograph it tonight.


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 Post subject: Re: Purchased Tsavorites that do not register red Chelsea fi
PostPosted: Mon Nov 26, 2012 10:49 pm 
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Absorption in red region (600-700 nm) and blue region (400-500 nm) is why the gem looks green. In the grossular spectra shown halfway down this page, the peak light intensity occurs around 530-540 nm, which is the same green as the little ring in my icon.


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 Post subject: Re: Purchased Tsavorites that do not register red Chelsea fi
PostPosted: Mon Nov 26, 2012 11:03 pm 
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Or, as I posted earlier:
Image

Your image should look more like the one on the right side with the OPL, :D


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 Post subject: Re: Purchased Tsavorites that do not register red Chelsea fi
PostPosted: Tue Nov 27, 2012 1:22 am 
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Here is the tsavorite rough purchased from prettyrock.com Image

Here's the rough mounted on LED Maglight:

Image

Here's the spectrum using OPL spectroscope:
Image

All images were shot using Sony NEX-5.


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 Post subject: Re: Purchased Tsavorites that do not register red Chelsea fi
PostPosted: Tue Nov 27, 2012 3:07 am 
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Here's a trillion tsavorite (the original gem that started this post).
Image

I shot these photos by holding my camera in my right hand (too lazy to get the tripod out) and shooting about 12 inches away from my 6$ loupe. The gem is lit by my LED pen light.

Image

Here's one of my shots close up:
Image
These inclusion occupied a flat plane that cut diagonally down the gem. It looked kindof like a fingerprint.

Here's another close up:
Image
These inclusions occupied an outside corner.

I tried to shoot the spectrum but it only looked like there wasn't any absorption lines. I will try again using my Ipad.


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 Post subject: Re: Purchased Tsavorites that do not register red Chelsea fi
PostPosted: Tue Nov 27, 2012 3:34 am 
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Here's the tsavorite trillion spectrum taken with the Ipad.
Image

Didn't really capture what I saw - strong absorption in the blue side mostly, depending on what method I used. When I viewed the stone in another way, there seem to have fuzzy absorption line in between the green and blue zones.


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 Post subject: Re: Purchased Tsavorites that do not register red Chelsea fi
PostPosted: Tue Nov 27, 2012 4:22 pm 
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I use the Chelsea filter all the time when buying rough, and find it very useful to separate non Chrome green tourmaline from chrome when going through a parcel. You are right, you tsavorite should show red under the filter.

I think your problem is your light source. You need to use a good old fashioned incandescent light. If you are using these new CFL bulbs or even most LED your results will not be good. Hold the filter right up to your eye, and with the stone on some white tissue hold it under a strong incandescent light.

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 Post subject: Re: Purchased Tsavorites that do not register red Chelsea fi
PostPosted: Tue Nov 27, 2012 6:00 pm 
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I've been rummaging around my house and we don't have tungsten flashlight. My tsavorite rough also does not glow red under chelsea filter.

I've taken a few more photos, this time using a Canon PowerShot (my Sony battery is dead) and also using my son's student micro cope. It has a really annoying black pointer in the middle of the viewfinder.

tsavorite rough @ 100x (10x eyepiece + 10x power)
Image

Here's a close-up:
Image

I also shot a sapphire rough:
Image

Here's the sapphire under the microscope:
Image

Here's the inclusion close-up:
Image

Are these inclusions typical of tsvorites (kindof pebbly)? What is the inclusion in the sapphire?


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 Post subject: Re: Purchased Tsavorites that do not register red Chelsea fi
PostPosted: Wed Nov 28, 2012 1:03 am 
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Until you have a proper light, using either the Chelsea filter or spectroscope is a waste of time.

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 Post subject: Re: Purchased Tsavorites that do not register red Chelsea fi
PostPosted: Wed Nov 28, 2012 2:25 am 
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Ok. Will take more spectra photos when I purchase tungsten flashlight. Do you have any opinion about the tsavorite inclusions? They do not look like bubbles. I can't ID the shape since I'm new at this. I think the sapphire inclusion would be difficult to ID without some kind of high end tool unless it is common to that kind of stone.


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 Post subject: Re: Purchased Tsavorites that do not register red Chelsea fi
PostPosted: Wed Nov 28, 2012 2:32 am 
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I found an old halogen desk lamp and tested my tsavorite rough and trillion. They glowed pink! :)


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