Treated sapphires and treated rubies are prevalent on the jewelry scene. You’ll see them in our store in our estate jewelry pieces (especially the rubies) and on smaller gemstone designs. Most of our large sapphire rings and earrings are untreated, because of the value of the piece. But heat treated gems are a gorgeous, less expensive way to get the look of a bright red ruby or a rich blue sapphire. It does affect the resale value of the piece, but if you’re buying for keeps and you’re on a budget, a heat treated gem can stretch your dollar. When it comes to this month’s lovely red birthstone, treatments are common – but they’re not always properly disclosed.
The most common treatment we see is heat, though lead and glass filled rubies do pop up from time to time in our buyers’ offices, especially when they’re evaluating vintage pieces. This treatment is used to fill fractures and give the stone a cleaner appearance. As with all treated stones, there’s nothing inherently wrong with improving the stone’s look. Think of it like cosmetic surgery. It’s when your jeweler doesn’t disclose every.single.treatment. immediately that you have a problem. Many treatments compromise the stone’s integrity and durability, and if you thought you had a natural, untreated ruby, and dropped it into your jewelry cleaner, it would destroy a filled ruby. Last year, the Today Show did a hidden camera shopping spree to shine a spotlight on this disclosure (and price gouging) issue. While they won’t deign to call these “rubies” at all, a gemologist does explain what’s going on:
“…Lead-glass rubies are not found naturally in the earth, but are instead made using a combination of low-quality corundum, the mineral found in ruby, which is then infused with high amounts of lead glass. The mixture is heated at high temperatures and then cooled, cut and polished. Smith says these lead-glass stones lack the durability and value of genuine rubies.”
And how to immediately spot a treated ruby? If you can see air bubbles with a loupe, you’re looking at a fracture filled stone.