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 Post subject: Mali garnet color change
PostPosted: Fri Apr 24, 2020 1:29 pm 
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I have some garnets from mali that show strong color change from deep gold(incandescent) to yellow with a hint of green or green or bright yellow(sunlight). One of the faceters in a fb group I'm in said it's due to the magnesium and manganese. Does anyone have experience with these types of stones?


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 Post subject: Re: Mali garnet color change
PostPosted: Fri Apr 24, 2020 3:45 pm 
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I would call that color shift, more than color change. The new LED style light sources that produce just a narrow spectrum of light tend to make almost all stone shift these days.


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 Post subject: Re: Mali garnet color change
PostPosted: Fri Apr 24, 2020 6:03 pm 
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It's the same in the sun.


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 Post subject: Re: Mali garnet color change
PostPosted: Fri Apr 24, 2020 6:20 pm 
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Yes, of course it would be. Most LED is very close to sunlight.

The difference between color shift and color change is:

your stone remains in the yellow/orange color range shifting between more yellow than orange to more orange than yellow.

A color change stone changes from something like a blue green to a purple red. This represent a complete change of primary color.

Almost all garnets color shift. Very few color change.


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 Post subject: Re: Mali garnet color change
PostPosted: Fri Apr 24, 2020 6:53 pm 
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Ok I understand. Thanks! I see what you mean now. It looked green before but it doesn't now that its faceted, is the green just from the light also? Or is it not green at all?


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 Post subject: Re: Mali garnet color change
PostPosted: Fri Apr 24, 2020 6:58 pm 
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pics faceted


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 Post subject: Re: Mali garnet color change
PostPosted: Fri Apr 24, 2020 9:36 pm 
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Things like color shift are far more prominent in transmitted light which is what you see in rough. After the stone is cut you are seeing reflected light which tends to minimize the shift. That is why it is often suggested that a slight window can actually improve clore change/shift gemstones.


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 Post subject: Re: Mali garnet color change
PostPosted: Fri Apr 24, 2020 11:44 pm 
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Thank you! I will look for some cuts for color shift stones.


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