About three years ago we stopped using diamonds an out main central gem! We couldn’t trust anymore that we buy (and sell) what you and we paid for. Lab created diamonds (or sapphires and Ruby) are not the problem, The problem is the lab created diamonds was sold with gemological certificates as natural. Our primary production was always sapphire, so it was quite an easy step. Counterfeit GIA certificates issued by an official GIA lab. GIA has invalidated grading reports for 1,042 diamonds submitted primarily to our grading laboratory in India
To my best knowledge Lab created melee (the small tiny diamonds) was not produced. It is no longer true! Lately, lots of Lab Created Diamond are sold as natural with a GIA certificate, read about it
Alibaba, Lab-Grown Diamonds, and the Specter of a GIA Report Aftermarket read here
The naked truth is that the jewelry shop, jeweler/factory is so far from the lapidary (almost 100% in India) in the production chain, that there is no way he can be 100% sure that what he bought is what he got. When authentic GIA is a forged and lapidaries mix synthetic with the natural, no one can trust the diamond industry anymore.
As a result, we started to use extra white high-quality small sapphire in some of our rings. With the sapphires we 100% sure that the gems are natural. We just shipped a few rings with 1.5mm sapphires instead of smaller diamonds, The results are great.