Garnet and is one of the most prized of garnet varieties. Topazolite is a golden-yellow variety and melanite is a black variety. Grossular is a calcium-aluminium garnet with the formula CaAl(SiO), though the calcium may in part be replaced by ferrous iron and the aluminium by ferric iron. 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. Because of its inferior hardness to zircon, which the yellow crystals resemble, they have also
Yttrium aluminium garnet has low heat sensitivity. As a synthetic gemstone YAG has numerous varietal and trade names, as well as a number of misnomers. Synonymous names include: "alexite", "amamite", "circolite", "dia-bud", "diamite", "diamogem", "diamonair", "diamone", "diamonique", "diamonite", "diamonte", "di'yag", "geminair", "gemonair", "kimberly", "Linde simulated diamond", "nier-gem", "regalair", "replique", "somerset", "triamond", "YAIG", and "yttrium garnet". Production for the gem trade decreased after the introduction of synthetic cubic zirconia; there was little production. Some demand exists as synthetic garnet, and for designs where the very high refractive index of cubic zirconia is not desirable. Neodymium-doped YAG (Nd:YAG) was developed in the early 1960s, and