Hi. I’d like to know about glass filled rubies. Are they safe to be used? Are a lot of jewelers using them?
Hi, for about 10 years now there has been glassed filled ruby being treated in Thailand (not sure elsewhere) there are literally tons a year coming out of Thailand and across the world. So you could say there are tons of the glass filled ruby right now in jewellery all over the world. Reputable Jewellers would advise customers that the ruby is glassed filled or “Fissure Filled”. The GIA call this treated ruby a composite ruby which means they do not recognise it as a natural gemstone but a gem that has been put together as it has been filled with so much lead glass. It is okay in Jewellery as long as no high heat is applied to it or subjected to cleaning in Ultra sonic etc.
Be aware that GIA calls glass filled rubies imitations rather than treated rubies. They are used in low end jewelry. My Gemworld price guide gives an upper limit of $200/ct for a glass filled ruby in a 5 to 20 ct size, whereas even a 0.25 to 0.49 ct natural ruby, heat treated, would be $200/ct in a grade 5 out of 10. A five carat ruby in a grade 5 out of 10 would cost a minimum of $2500/ct and a top grade 1 ct ruby would start at $6600/ct. So you are really talking about apples and oranges here. As noted already, you can’t solder near the glass filled ruby and you can ruin it cleaning it in an ultrasonic. If it got chipped or scratched, it would be difficult to recut. In my opinion, it’s junk. I would much rather have a premium synthetic, which would be durable, about flawless and able to be cleaned.
Thank you for the information.