Certification and Sapphires

[MustangFan]

I am going to look at more sapphires today, and the jeweler said that gemstones don''t already come with certification, but his gemologist can have papers made up. Is this true? I don''t know what to believe anymore. I hear one thing someone tells me another. I''ve been reading a book that talks all about the importance of certs.

 

[TheDoctor]

Most coloured gemstones are traded and sold without certs, even some of the most valuable ones. It''s common to have the sale riding on an independent appraisal by a respected gemologist. Don''t fear un-certed stones, just have the purchase conditional on an independent appraisal from a GG of your choosing.

 

[riogems]

Yes - most color stones (99%+) do not come with a lab report. (Or they have an unreliable report only for export.) That last point is important, because it means that most reports are not worth more than the paper they are printed on. There are some trusted labs -- GIA, AGTA, etc.... (but for every trusted lab - there are a dozen labs that aren''t so good).

From an industry perspective -- the labs (US) charge too much as a percentage of the color stone value -- and the report does not grade it in terms of quality factors (like a diamond report does - color, clarity, cut, polish, symmetry, etc...). A color stone report typically will just verify that it is a sapphire, and confirm the weight and dimensions. For sapphire, it might say the origin of the stone (typically if you pay more for this). For a sapphire, it also might say if there is evidence of heat treatment. However, you have to pay even more if you want to test if it was Be-treated too. All-in-all, a trusty US-lab report is a pricey proposition. Most gem dealers will not get them, and will let their customers pay for it if they want one. By all means, if you''re treating this purchase with as much attention (and a significant amount of money) as buying an engagement "diamond," you may want to consider a lab report. Or, if you''re looking to only by an untreated sapphire, you should consider getting a lab report (and you understand that even if there is no evidence of heating it may have been heated). Otherwise, you should be satisfied by just confirming that it is actually a sapphire.

 

[colorchange]

Date: 4/26/2006 1:13:11 PM
Author: riogems
Yes - most color stones (99%+) do not come with a lab report. (Or they have an unreliable report only for export.) That last point is important, because it means that most reports are not worth more than the paper they are printed on. There are some trusted labs -- GIA, AGTA, etc.... (but for every trusted lab - there are a dozen labs that aren''t so good).

You seem to inply Thaï labs aren''t good, while, for using them oftem, AIGS and GIT are just as reliable as AGTA and GIA on colored stones (I don''t know about diamond that I don''t trade)...

 

[riogems]

Colorchange -- it is not feasible for this person to send the gem to a Thai lab from the US. If the stone was certified in Thailand before making its way to the US, that would be a different story. I''m sure you''re aware of the Thai VAT and government license required to import gemstones. This is what I meant by US... not that Thai labs are bad. There are good labs in other countries as well.