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Sapphires are one of the few gemstones that produce a star shape of four to six light-reflecting rays across the center of a cut stone. With its perfect color, cut and luminous star, the lab-made Lindy, or Linde, star sapphire is just too good to be natural. The perfection of its star is what makes the Linde sapphire stand out as a synthetic among natural sapphires.

Linde Star Sapphire History

The Linde Division of the Union Carbide Corporation in the United States first began lab-producing and marketing their star sapphires in the late 1940s. Each Linde stone has a small "L" imprinted on its bottom. The stone is cut in a smooth cabochon setting with no facets, which enhances the appearance of the star.

Difference Between Linde and Natural Sapphires

A Linde sapphire's star has thin, perfectly even rays that are so clear some jewelry experts say they appear "painted on." The star is visible even in dim light and doesn't move relative to a light source. In contrast, a natural sapphire's star has thicker, slightly uneven rays, and the star moves to follow the light.