What is a characteristic feature of synthetic opal?

A characteristic feature of synthetic opal is the snakeskin structural pattern. This feature arises from the way synthetic opal is manufactured. The production process often involves creating layers of silica spheres that can organize in a manner similar to a snakeskin, giving it a unique appearance that can sometimes be distinctly different from natural opal.

Natural opals generally display a more chaotic arrangement of silica, leading to different types of play-of-color patterns and inclusions. The snakeskin pattern is a hallmark of many synthetic versions, helping gemologists identify and differentiate synthetic opal from its natural counterpart.

The inclusion of bubble-like features, color zoning, and fluorescence may also be present in various opals, but these do not serve as significant identifiers of synthetic opal, particularly when compared to the distinctive snakeskin pattern associated with synthetic varieties.