Grossular Garnet, from Zacatecas, Mexico (REF:GAR1)

There are more than twenty types Garnets. The six more common types:- Pyrope, Almandine, Spessartine, Grossular, Andradite, and Uvarovite.

All are aluminium or calcium silictes chemical compositions Silicon, Oxygen, Aluminium &  Calcium, which may be joined by metals, such as Chromium, Iron, Magnesium or Manganese, and other colour-causing elements such as vanadium.

  

Grossular is a calcium-aluminium species of the garnet group of minerals. 

The name grossular is derived from the botanical name for the gooseberry, grossularia, in reference to the green garnet of this composition that is found in Siberia. Other shades include cinnamon brown (cinnamon stone variety), red, and yellow. Grossular is a gemstone.