Amethyst Buying and the Four Cs

The IGS amethyst value listing has price guidelines for faceted and cabbed gems.

With a hardness of 7 and lack of inclusions, amethyst makes a durable stone fit for any gem setting. Combining versatility and beauty, amethysts make excellent choices for jewelry or decorative pieces.

Color

Amethyst receives its purple color from its iron content and natural irradiation under the Earth’s surface. Transparent gems are abundant. While high-quality amethysts aren’t difficult to find, exceptional specimens are still rare.

As with other colored gemstones, hue, tone, and saturation factors have the most impact on cost. A high-quality amethyst will show even color, without visible zoning. Amethysts range in color from light, pinkish purple stones to deep grape hues.

Siberian Color

The most highly valued amethysts are “Siberian quality.” This term no longer refers to the stone’s origin. Rather, gemologists use it to refer to stones that exhibit red and blue flashes on deep purple color.

Darker Gems

Consumers generally favor darker stones, ideally with 75-80% tone. Secondary blue hues, up to 20%, add depth to the gem. Secondary red hues may be present under incandescent light. Their presence indicates a truly exceptional…