They look like real rubies, with vibrant color and brilliant sparkles. But “composite rubies” aren’t natural; their beauty was created in a factory.
A composite ruby is made from multiple pieces of poor quality corundum(the mineral we call a ruby when it’s red) bonded together with tinted glass.
“Sometimes there’s more ruby than glass, sometimes there’s more glass than ruby,” says Christopher Smith at the American Gemological Laboratories in New York.
Most shoppers have never heard about this unnatural process which has only been around for a few years. They assume all rubies come out of the ground as a single stone. Even if you know about composites, it’s almost impossible to spot one with the naked eye. You need to use a jeweler’s loupe or look under a microscope to see the telltale signs.
Virginia Johnson of Lynchburg, Va. paid about $20,000 for a “ruby” necklace and several “ruby” rings she saw on a cable TV show. She says “they look really nice,” but they’re not the “all natural” stones she ordered.
It wasn’t until she had the jewelry appraised for insurance purposes that Johnson learned the truth: Some of her supposedly “natural” rubies were more than half composite material.
“It was a real shock,” Johnson says. “When they say ‘all natural’ and they’re not, that’s a problem.”
Proper disclosure is hit-and-miss
There’s nothing wrong with selling composite gemstones as long as customers are specifically told the stones are composite. That’s required under Federal Trade Commission guidelines.
Unfortunately, that doesn’t always happen. And when it doesn’t, the buyer might never know they’re getting a manufactured stone worth significantly less than the real thing.
Many composite stones come from Thailand where they sell for just a dollar or two a carat.
“You can find 50 carat composites or ½ carat composites. It’s all across the board,” says Kenneth Scarratt with the Gemological Institute of America laboratory in Bangkok. And he points out, “There are no geographic boundaries to this. It’s everywhere.”
Most rubies are treated in some way
Buy almost any ruby and you should assume it’s been treated in some way to improve its appearance. Natural bright red rubies (not treated in any way) are so rare only the wealthy can afford them.
Rubies have been heat-treated – to enhance color and bring out their brilliance – for decades. This is a well-accepted practice within the industry.
Some stones with minor fractures are filled with leaded glass to improve their appearance. They sell for significantly less than other types of treated rubies.
Composite takes treatment to a whole new level.
“A composite is not a single ruby that has been treated in some way. It is multiple pieces bonded together with tinted glass,” explains , author of “Jewelry and Gems: The Buying Guide.”
Matlins is on the Board of the Accredited Gemologists Association. She shops undercover at gem shows and department stores and find few sellers who are upfront about their composites.
“They have not stated what we are buying. They have not said special care is needed. In fact, they have told me just the opposite; that these are natural, untreated with no special care required.”
Unlike real rubies, composites are unstable. Because a significant portion of the stone is glass, composites need to be handled with special care or they can be damaged.
Craig Lynch, an accredited senior gemologist at Ouellet and Lynch in Phoenix, put a composite into the mild acid solution jewelers use to clean ruby rings.
“It seriously damaged the stone within two minutes,” he says. “You could put a real stone in that solution for weeks or months and it would not be damaged.”
Lynch also found that lemon juice can degrade a composite in a couple of days. Household cleaners could have the same effect.
“So there is a huge difference between the real thing and what the material is trying to imitate,” Lynch says.
How to protect yourself
With so many composites on the market, you need to make sure you know what you’re buying. Your best bet is to stick with reputable jewelers, who have the training to know what they’re selling.
“If you purchase from a reputable jeweler, we’re going to stand behind what we sell,” says Bev Hori, vice president of education at Ben Bridge Jewelers.
Gemologist Lynch says most composite rubies are purchased through non-traditional marketplaces: online jewelry sites and cable TV shows, Internet and traveling auctions, gem shows and even cruise ships. He also sees clients get burned on trips to foreign countries.
Wherever you shop, Matlins says you must ask several essential questions. Was this stone treated in any way, and if so, how? Is this a composite ruby? Is any special care required? Equally important, make sure all of the answers are on the receipt. That way, you’ll have documentation if there is a dispute after the sale. If a significant amount of money is involved, you’d be smart to have the item appraised right away.