Sapphires Natural, Treated, & Synthetic

When selecting colored gemstones—especially sapphires—it’s essential to understand the difference between the terms natural and untreated. These are often confused, yet they refer to two distinct aspects of a gemstone’s identity. While the ideal sapphire would be both natural and untreated, such stones are exceptionally rare on today’s market.

A natural sapphire is one that formed naturally within the earth over millions of years—it is not lab-created. An untreated sapphire means that, aside from being cut and polished (standard practices for any gemstone), it has not been subjected to any processes intended to enhance its color or clarity, such as heating or chemical treatment.

Untreated Sapphires:
Natural, untreated sapphires are among the rarest and most sought-after gems in the world. These stones have not undergone any enhancement to improve color or clarity, allowing their natural beauty to shine through. Untreated sapphires with strong color, good transparency, and minimal inclusions are exceptionally rare—particularly in larger sizes—and they command premium prices in the market. Their geological purity and authenticity make them especially desirable to collectors and connoisseurs.

Treated Sapphires:
The majority of sapphires available on the market today have been heat-treated, a long-standing and widely accepted method used to enhance both color and clarity. This process is stable, permanent, and considered standard in the industry. Light heat treatment typically does not significantly affect a sapphire’s value, especially when the resulting color and clarity are exceptional. However, sapphires subjected to more intensive or less traditional treatments—such as diffusion, fracture-filling, or beryllium treatment—may be less valuable and should be clearly disclosed to the buyer.

Synthetic Sapphires:
Synthetic sapphires are lab-grown gemstones that have the same chemical composition, crystal structure, and optical properties as natural sapphires. They can display beautiful color and clarity—sometimes even better than their natural counterparts—but they lack the rarity and natural formation history of earth-mined stones. As a result, synthetic sapphires are considerably less valuable than natural ones, even if visually identical.

Sapphire Simulants:
Sapphire simulants are materials that imitate the look of a sapphire but are composed of completely different substances. These include blue glass, cubic zirconia, and synthetic spinel. While they may resemble real sapphires at first glance, simulants do not share the same physical or optical properties. Their value is minimal, and they are generally used in costume or fashion jewelry, not in fine gemstone settings.