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**New York State Geological Symbols**
Type	Symbol	Year Est.
State Gem	Garnet	1969
State Fossil	Eurypterus remipes	1984

State Gem: Garnet

Garnet is typically thought of as one specific mineral, however garnet is actually a series of very similar minerals. This mineral series varies in chemical composition, resulting in different mineral names, however the chemical composition of all of the garnets share a generalized chemical composition: X₃Y₂(SiO₄)₃, where "X" can be Ca, Mg, Fe²⁺, or Mn²⁺, and "Y" can be Al, Fe³⁺, Mn³⁺, V³⁺, or Cr³⁺. Along with the different chemical compositions, there are different colors and hardnesses associated with each one as well. Crystals of garnet typically form in 12-sided "balls", that can be easy to identify within the rocks that they are found in. The name "garnet" comes from the Latin, "granatus" meaning "like a grain" because of this ball-crystal habit. Garnet is formed from the metamorphism of shale minerals, and can be found in most foliated metamorphic rocks such as schist and gneiss. Garnets can also be found in some igneous rocks including granites and granitic pegmatites. Garnet has been used as a gemstone since ancient Egypt, however recently garnet has obtained significant usage as an abrasive. Since garnet is a rather hard mineral and has no cleavage, it typically breaks into sharp edged fragments, and therefore produces a good grit for water-jet cutting or sandblasting. Garnet is a very common mineral and even high grade gemstone quality specimens can be fairly cheap.