are any precious or semi-precious stones,
whether as mined, or cut and polished.
terms "gem" and "gemstone" mean any mineral
or organic materia used for personal adornment,
display, or object of art because it possesses
beauty, rarity, and durability.
Of the 2,700 mineral species, only about
100 possess all these attributes. Silicates
compose the largest group of gemstones;
oxides and quartz compose the second largest.