Fine sapphires of Kashmir or Burmese origin typically fare well but large, incredibly rare stones can sell for millions. A well-cut sapphire will display its color to its best ability, while still enhancing luster and brilliance. Sapphires vary in density, so they are measured by size as well as carat weight. Sapphire color is evaluated on three qualities: hue, tone, and saturation.
Sapphires form in an environment rich with trace minerals, which affect sapphire clarity. Sapphires are among the earliest known gemstones and are highly valued for their durability. Sapphires are commonly heat-treated to improve color, clarity, and overall appearance.