When you buy a sapphire or ruby, you sort of expect that what you see is what you get, right? Perhaps you have a distant vision of the stone being dug out of the earth by reverent hands, carried carefully to the workshop of a skilled cutter, meticulously polished, and shipped straight to you.
If you shop with The Natural Sapphire Company, your mental image is actually pretty accurate.
However, if you buy uncertified sapphires … there might have been a few stops along the way. 99% of sapphires in the market today are 99% of sapphires on the market are treated with processes like color diffusion, fracture filling, or being heated to extremes.
So what does all of that mean?
Well, if you buy a color diffused sapphire, you’re buying a once-colorless stone that’s been transformed to a beautiful blue … at least to the depth of half a millimeter. You see, sapphire’s main chemical composition derives from aluminum oxide, but its color comes from trace elements like iron and titanium. Those same chemicals are combined in the diffusion process in a pan, and the stones are added to it, and subjected to intense heat. This process “bakes” the sapphire, bringing a high concentration of its trace elements to the surface. Color diffused sapphires can be beautiful … so long as you never repolish them, as it would quickly be revealed that the Emperor had no brightly colored sapphires.
Fracture filled or “composite” gemstones have been much in the news recently: afflicting rubies in particular, this practice consists of superheating rubies and packing their cavities with lead glass, which possesses a very similar refractive index. The fracture-filling process can be relatively minor and an incidental byproduct of the more common heat treatment, or it can be deliberate and result in a hugely altered ruby … and a hugely altered price-tag. However, now there’s an additional element: some rubies being sold on the market are “multiple pieces of typically low-quality corundum, fused together by colored glass and often containing more glass than corundum.” (National Jeweler Network) To use a potentially unpalatable metaphor, if natural rubies are a treat along the lines of the best filet mignon, composite rubies are like hot dogs from a street vender’s cart: mysterious in their contents, highly unnatural, and more than likely to leave you with a bad case of indigestion.
Heating is the most common treatment, dating back before the Classical period: as with many things, it’s as much a question of degree as anything else. While mild heat treating may moderately improve a stone’s color or clarity, high heat literally melts the inclusions within the stone, producing a characteristic “dead” appearance. And, of course, any heat reduces the value and rarity of the stone in question: it’s up to the buyer to decide how that affects their desire for a bigger, more affordable stone.
Luckily, there are alternatives … like our wares. We disclose all information, provide extensive testing and full certification, and concentrate on providing the rarest, best, and most beautiful. Who could resist goods like these natural sapphires and untreated rubies?
Natural blue sapphire B3637, unique rubies U2353 and U559, and natural blue sapphire B2767: it’s a spectrum of natural delight