What is the primary definition of a gem?

The primary definition of a gem emphasizes its nature as a natural material that consists of one or more kinds of mineral crystals. This highlights the essential characteristics that qualify a substance as a gem, focusing on its mineral composition. Gems are typically formed through geological processes and can be composed of varied minerals or combinations thereof.

While beauty and rarity are significant factors in the valuation of gems, these qualities are often subjective and vary across different contexts and cultures. The durability of a gem is important, but it is not a defining characteristic that sets it apart as a gem from other materials.

Regarding synthetic materials, they are designed to mimic the appearance of natural gems but do not fit the primary definition of a gem since they are not formed naturally. Moreover, many minerals found abundantly in nature do not meet the criteria of beauty, rarity, or durability that are often associated with gems, reinforcing the importance of mineral composition as the primary defining feature.