Elkahia journal / The foundations
A mineral, a metal, a gemstone
Three related ideas, with three different meanings.
An element is defined by its atomic number. Gold, iron and titanium are elements with metallic properties. A mineral species, in contrast, is identified through its chemical composition and structure. Some native metals, including gold, also occur as minerals, so the same word can appear in both parts of this archive.
A gem name does not always identify a separate mineral species. Ruby and sapphire are varieties of corundum. Emerald and aquamarine are varieties of beryl. The gem-name view helps you move from the name used in jewellery to the scientific species record.
Not every mineral is suitable for jewellery. Rarity, crystal size, durability and optical properties all influence whether a material can be cut and worn. This encyclopedia describes materials; inclusion in the catalog does not mean that a material is offered for sale.