What is the primary use of specific gravity in gemology?

Specific gravity is a crucial property in gemology that helps gemologists identify gemstones. This measurement, which compares the density of a gemstone to the density of water, provides valuable information about the stone's identity since each mineral has a characteristic specific gravity. When examining a gemstone, determining its specific gravity can help distinguish it from other stones with similar appearances but different densities.

In the identification process, a gemologist may use specific gravity alongside other tests such as refractive index and surface characteristics. By understanding the specific gravity of a stone in question, gemologists can narrow down the possibilities of what it might be, aiding in accurate identification.

Other options, while they may relate to different aspects of gemology, do not accurately reflect the primary use of specific gravity. For instance, measuring the size of gemstones reflects dimensional assessment rather than density, evaluating quality pertains to factors like clarity and color rather than density measure, and calculating market value involves various other economic factors rather than just physical properties like specific gravity.