Since gemstones come in a variety of colors, patterns, and shapes, there are several different methods out there to classify them. For example, some of the classifications include dividing the gemstones into categories based on their chemical composition, or among precious and semi-precious gems, diamonds and colored stones, or organic and inorganic gems. The rank of a gemstone in any one of these classifications can affect its overall value.

Every gemstone is surrounded by scientific characteristics and terms you must know to identify their value and uniqueness. This scale provides a list of accurate RI – the single most important piece of information when it comes to identifying an unknown stone.

When it comes to weighting a gemstone, gemologists use the Specific Gravity along with other measurements to estimate the carat weight of a stone. The Specific Gravity is simply the number of times heavier a gemstone ( of any volume) is than an equal amount of water or put simply the overall ratio of the gemstone density to the water density.

Created over 170 years ago and used around the world today to distinguish minerals, the Mohs Hardness Scale will let you discover how hard or soft a gemstone is. It begins with talc at 1 as the softest and ends with diamonds at 10 for being the hardest. The hardness of a gemstone can easily be determined through scratching it with a harder substance; the higher the number, the harder the mineral.