When the natural crystal is beautiful, it requires no processing beyond polishing.
The brilliance of an untreated Sri Lankan sapphire is in a class of its own.
Traditionally, the most favored color for Sapphire is the rich and soft "cornflower blue" seen in Kashmir stones. Though there is virtually no mining in Kashmir now, sapphires that approach this color are found in Sri Lanka.

Some of the sapphires that are mined and polished in Sri Lanka are not heated. The photograph on the next page shows an untreated Sri Lankan sapphire. It is transparent with a somewhat velvety appearance, giving it a unique character. A tone level of 5 makes it very attractive even under weak lighting. Darker stones with tone levels of 6 or 7 exhibit a unique and rare beauty under stone lighting, but do not appear as beautiful under weak light. The sapphire in the ring below is also untreated. It has a somewhat light tone of 4, but shines beautifully even from a distance. As with Sri Lanka, there are sapphires from Myanmar and Kashmir that are not heat-treated.

Crystals that have a beautiful color in their natural state do not require any processing beyond polishing. In general, however, most sapphire crystals are not transparent, or they are too dark or too light. These crystals have their transparency and tone of color adjusted through heating at temperatures ranging from several hundred to nearly two thousand degrees Celsius.
Around 1977, it was discovered that the near-colorless Sri Lankan sapphire rough called "geuda," which had been routinely discarded until then, would become a gorgeous blue color when heat-treated. Large quantities of this rough material were taken to Thailand, where they were heated and polished. From there they were introduced to the world market, where they have succeeded in capturing the largest share. Though their beauty achieved widespread recognition, deals of their heat treatment have not reached the general public.

There are subtle difference between the liveliness of a naturally beautiful color and that of a beautiful color brought about through heat treatment. And individual's preference is a personal decision, but one that should be made with the knowledge of whether the beauty is natural or a result of treatment.

Sapphires from Tanzania and Madagascar began appearing on the market in the 1990s, and some of these show a fine quality similar to Sri Lankan sapphire. Most large sapphires, however, are from Sri Lanka.
Ring, Platinum
Sri Lankan Sapphire 1 pc
26.00 ct
Diamond 2 pc
US $130,000