This oval lab-created star ruby cabochon is economical and versatile. Place them in PMC+™ and PMC3™ designs; they’ll withstand the heat of firing. Star ruby is created from lab-grown red corundum and its distinctive six-ray star, easily visible under any light source, is the result of the introduction of titanium into the process as the mineral forms. The titanium forms inclusions in the forming mineral structure that, under intense heat and pressure, produce the appearance of the star. The star effect, known as “asterism,” tends to be more defined and easier to see in a created stone.