Feldspar

Because feldspar is abundant, carat weight alone is not usually a major value driver except for fine-quality optical varieties in larger sizes. Large, clean moonstones, labradorites or sunstones with strong optical effects can command higher prices.

Color and optical effects are central: blue or multicolored schiller in labradorite, strong blue adularescence in moonstone or vivid aventurescent flashes in sunstone substantially increase value. Plain, dull body color with weak phenomena is much less desirable.

Clarity expectations depend on variety, but in general, stones should be free from distracting cracks, pits or cloudiness that interferes with light play. Some inclusions, such as copper platelets in Oregon sunstone, are actually necessary for desirable effects.

Feldspar is often cut en cabochon to emphasize adularescence or aventurescence, or faceted when body color and transparency warrant. Correct orientation to maximize optical phenomena and a smooth, well-proportioned cut with good polish are essential to high value.

Feldspar minerals are among the most abundant in Earth's crust, with numerous deposits worldwide. Gem-quality material for specific feldspar varieties comes from India, Sri Lanka, Madagascar, Tanzania, the United States and other countries, with production generally sufficient for current demand.

Demand is steady and broad-based, driven by feldspar's affordability and unique optical effects that fit well with bohemian and artisanal jewelry trends. Specific varieties like Oregon sunstone and high-quality rainbow moonstone have gained dedicated followings.

Feldspar varieties with pronounced optical effects have seen renewed popularity in designer and metaphysical markets, leading to firmer prices for top-quality material, while lower grades remain inexpensive.