The characteristics that make gems attractive are basically three:

1 ) Beauty, a concept that is undoubtedly subjective and subject to the vagaries of fashion, but with objective components, such as color, brightness, transparency, dispersion and other optical properties.

2 ) Its durability, or ability to resist shocks and friction with other materials without major damage. In this sense, it is known that the admiration that the ancients felt for the diamond was due, not to its shine, but to its hardness.

3 ) The shortage or rarity is valued in a gem, which gives it the feeling of power and individuality.