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Composite "Rubies" Pose Serious Problem for Consumers

By Antoinette Matlins, PG

For thousands of years, rubies have been sought and treasured, prized as one of the most valuable of all things on Earth. A fine ruby has everything a precious stone should have — magnificent color, shimmering brilliance, extreme rarity, and excellent hardness and overall durability. Such stones command high prices, and the finest and rarest rubies are among the costliest of all gems, costlier than sapphires, emeralds, and even the finest colorless diamonds. Today, however, an increasing number of people—both in America and abroad—are finding that the "ruby" they purchased is not what they thought it was when they bought it. In fact, what they are buying is often not even a "single" stone, but a composition of multiple pieces of extremely poor quality corundum (the mineral known as "ruby" when it occurs in a lovely red color and "sapphire" when it occurs in other lovely colors including blue and yellow) which has been fused together with colored glass!

bubbles in composite stone
Bubbles in composite stone

Internationally respected labs are now describing such stones as composite "ruby" and many have been found to contain more glass than anything else. Composite stones are not new, but these are produced in a different manner than old-fashioned composite stones, and as a result, went undetected until recently. The World Jewellery Confederation known as CIBJO (an affiliation of organizations from 40 nations and whose mission is, among other things, to protect consumers) does not recognize composite stones as genuine gemstones. CIBJO defines composite stones as: "artificial products composed of two or more, previously separate, parts or layers assembled by bonding or other artificial methods." And this is exactly what we find in composite "rubies."

In the USA, it is a violation of FTC guidelines to sell any composite stone without disclosing what it is. Furthermore, when a treatment reduces the durability of the stone, the FTC requires disclosure of this fact as well. Nonetheless, these stones are being sold extensively without any disclosure that they are composite, and without mention of the need for special care.

Composite "Rubies" are in a Class by Themselves … and Pose Serious Problems When Not Properly Identified

Composite rubies must be distinguished from other rubies, and it is important to understand what types of rubies are now available in order to grasp the full picture. Today there are two general categories of gemstones, including ruby: treated and natural (that is, not enhanced in any way). Rubies have been routinely enhanced by a variety of techniques for almost half a century, and are well accepted within the trade. The most common type of treatment for ruby is heating, which improves the color and clarity to varying degrees. Today anyone buying a ruby should assume it’s been heated (and possibly treated in other ways) unless there is documentation from a respected laboratory confirming that it is entirely natural. Natural rubies (that is, rubies that have not been enhanced in any way) are among the rarest of all things—an exceptional 8.60 carat natural ruby sold at auction for $3.6 million dollars, $465,000 per carat!

heat treated
Right composite was heat treated for 30 seconds

The price of this extraordinary gem reflected the extreme rarity of anything comparable in today’s market—its pure red color, high clarity, and brilliance, all found together in a stone of such large size. The price of this gem also reflects the underlying reason for the introduction of treatments: the increasing scarcity of beautiful rubies. This is what led to the introduction of techniques to improve the appearance of natural gems. Natural rubies of the finest color and clarity were disappearing; the mines were depleted and supply couldn’t keep up with demand. Heating techniques were introduced in an effort to provide beautiful rubies (and sapphires and other gems as well) at prices people could still afford. Otherwise, only the world’s wealthiest would be able to dream of owning magnificent rubies or other gems today!

In addition to the routine heating of ruby, there are various other treatments used today, and varying degrees of treatment. Treated rubies are priced according to the type of treatment used, how extensively it was treated, and the overall post-treatment appearance compared to that of other similarly treated rubies. There can be minor glass residue in small surface-reaching cracks, and when unsightly cracks detract from the beauty of an otherwise beautiful ruby, they can be filled with glass to reduce their visibility; these are called glass-filled rubies. With so many treatments now used on rubies, many fine jewelry stores only sell rubies that have been submitted to gem-testing laboratories and each stone is accompanied by laboratory documentation. When present, treatments are indicated on the reports.

flash effect
Reflected light on composite stone
shows bubbles & surface crazing/cracks

But "treated" rubies should not be confused with "rubies" made from multiple pieces of low-quality corundum fused together with tinted glass."Treated" rubies are single stones that have been improved in some way to look more attractive. Some were lovely even prior to treatment, the treatment simply having made them even more attractive. Composite rubies are an altogether different thing, much less durable, and of much lower value.

Composite rubies began to surface in the USA in 2008. By early 2009 they were appearing in disturbing numbers, often among military personnel returning home with sparkling "treasures" purchased at "bargain prices" while "close to the mines," never suspecting they were victims of a scam. Today they are being sold in department store chains, mass-merchandisers, on the internet, television shopping channels, and at auction. In most cases, the prices seem to be "bargains" by comparison to the cost of other rubies sold in other stores, when, in fact, nothing is farther from the truth. Since they are not genuine rubies, there can be no comparison.

While there is nothing wrong with buying a composite "ruby" as long as you know what you are buying and pay an appropriate price, such stones should sell for a small fraction of the price of treated rubies – we’ve seen them at gem shows for around $30 per carat – and buyers must be extremely cautious when wearing them or if taking then to a jeweler for re-setting. Failure to exercise care will result in these stones quickly deteriorating into something very unattractive. In some situations, they may actually crumble apart.

What Can Consumers Do?

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