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blue sapphire cert question

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partgypsy

Ideal_Rock
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I was looking at a certificate for a heat treated blue sapphire, and it stated:
"lw (long wavelength?) medium red, sw (short wavelength): none"

Can anyone tell me what is the significance of medium red lw?
 

Richard Sherwood

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Hi (part) gypsy. The LW & SW refers to longwave & shortwave ultra-violet light. It''s not something you''d generally notice to the eye, but just another gemological indication of the characteristics of the stone.

So this stone "glows" a medium red under longwave ultraviolet, but has no reaction under shortwave ultraviolet.

Sri Lankan sapphires in particular as well as some Thai-Cambodian and African sapphires have this reaction.

Do you know the country of origin of your stone?
 

partgypsy

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Thanks for the info! I don''t own this stone, just thought it was pretty (on the web) and was looking at its cert. It is labeled as a ceylon sapphire, disclosed as heat treated, but was curious if this signified some kind of treatment other than heat, and I guess also if "lw medium red" had any adverse effect on its visual appearance. I''ve heard of rubies having red flouresence, but not blue sapphires.
 

Richard Sherwood

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Date: 4/10/2007 5:29:31 PM
Author: part gypsy
It is labeled as a ceylon sapphire, disclosed as heat treated, but was curious if this signified some kind of treatment other than heat, and I guess also if ''lw medium red'' had any adverse effect on its visual appearance. I''ve heard of rubies having red flouresence, but not blue sapphires.
Ceylon (Sri Lankan) sapphire often has this reaction under longwave ultraviolet light. There is no negative influence under normal lighting conditions.

It doesn not signify any other treatment than heat, and is just a normal reaction indicative of its origin.
 
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