Opal is the anniversary gemstone for the 14th and 18th years of marriage and is the birthstone of October. The word Opal comes from from "Upala" in Sanskrit (translated as treasured stone). It was called "Opalus" in Latin during the Roman Empire.

Opals are able to refract and reflect specific wavelengths of light. The interplay of different wavelengths of light gives opals their unique visual appeal, and makes them among of the most sought-after gemstones in the world. Opal has been precious and popular gemstone since Roman times. A beautiful opal called the orphanus was set in the crown of the Holy Roman Emperor.