Sapphires often have color zoning (which typically is undesirable) but this feature can be used to create cool effects when incorporated into the design. Here's an example where the blue color zoning in the culet was used to highlight the "flower" in this lab-created sapphire. ​

Finewater Gems is thrilled to announce its third place award in the Phenomenal Category of the American Gem Trade Association Spectrum Awards for this flawless 45.59 ct Ethiopian crystal opal. The design and cutting was performed over a period of several months to maximize color play, long-term stability, and beauty.
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The AGTA Spectrum Awards serve as the benchmark for industry design excellence and are the most important design competitions in the world for colored gemstones and cultured pearls. See the press release.

Unlike diamonds, there are no clarity standards for colored stones. "Eye-clean" is an informal definition used by many in the trade, but it is often misinterpreted by customers. Unlike most other vendors, Unlike most other vendors, we provide highly detailed photos that give a view similar to the use of a 10x loupe, so you may see inclusions in our photos that you would never notice in real life. With a bit of effort you may notice several tiny inclusions in this photo of a VS clarity amethyst. It is not flawless (nor is it claimed to be), but it is unlikely that anyone could see these inclusions at normal viewing distances without magnification - hence the description "eye-clean".

Inclusions in gemstones are generally not a desirable feature; however when the inclusions are very small and evenly distributed the light is even scattered and extinction reduced, as in the case of this unheated and "glowy" blue sapphire. ​

​These beautiful sapphires are the rarest and most desirable of all sapphires, and the original (and some say the only true variety) were from Sri Lanka. The color is similar to the lotus flower so the name in the Sinhalese language are padma (lotus) and raga (color), or padmaraga, modified over time to padparadscha. Some have also likened it to the color of the sunset or saffron. The combination of ruby and yellow sapphire produces a lovely orangey-pink to pinkish-orange color that is the critical defining characteristic, with no historical mention of tone or saturation. For unknown reasons an influential gemologist in the 1980’s decreed that they must have a pastel tone and low saturation, and this notion has stuck with Western gem labs and consumers. Fortunately the rest of the world still includes all sapphires in the color range as padparadschas, regardless of tone or saturation. I’ve been purchasing padparadschas in Sri Lanka for years, and I much prefer the rare and richly saturated medium toned stones.

If you need a special gemstone, just ask! As a GIA trained graduate gemologist with extensive travel experience and industry affiliations, I have excellent contacts in source countries such as Sri Lanka, Burma, Thailand and Colombia. Contact me for more details.