This is usually described as “royal blue.” Burma sapphire is set apart
by its transparency (crystal) and the vivid crispness of its hue. Kashmirs, by contrast, are a purer blue hue of a slightly more open (seventy-five percent) tone, with just five to ten percent purple, a hue often described as “cornflower.” 135

Kashmir stones often have what is described as a sleepy quality, a result of myriad numbers of microscopic inclusions known as flour which can be seen under the microscope. Light refracting through this microscopic Milky Way is diffused and this gives the stone an overall sleepy or fuzzy appearance. These inclusions also reflect light, dispersing it throughout the gem and thus reducing extinction. Kashmir sleepiness contrasts with the robust brilliance and transparency of a Burma stone.

Kashmir sapphire was found on
one side of one hill in the Indian
state it is named for, and was
effectively mined out by the 1930s.
Burmese sapphire has also been in short supply since the thirties. The new Burma ruby diggings at Mong Hsu produce almost no sapphire, and only a few stones per year find their way from the old mine areas of Moguk into the Bangkok market. Which is the best? Connoisseurs disagree, perhaps due to rarity, but fine Burmese stones cost at least fifty percent more than Ceylon sapphires, and Kashmir stones more than twice the price of Burmese.

Ceylon sapphire

Ceylon or Sri Lankan sapphire has been the quality standard bearer for the past half century. The Ceylon gem may look just like its Kashmir

and Burmese brethren, appearing either cornflower or royal blue; some have a Kashmir-like sleepy appearance. However, therelatively larger size of the inclusions causing the effect in Ceylon stones translates into a crisper sort of sleepiness that is qualitatively different, arguably less subtle than the same characteristic in stones from Kashmir. Ceylon sapphires can have a vivid royal blue like a fine Burma blue, but rarely show the crisp velvety transparent crystal and are a touch murkier than the best out of Burma.