Grossular Garnet: a Calcium Aluminium silicate of the Garnet Family whose formula is Ca3Al2(SiO4)3. It is often in combination with Andradite (calcium Iron Silicate). It crystallised in the Monometric System and can be found in dodecahedral crystals or in massive form; colourless, gray, yellow, pink, red, brown, green. 3.40-3.71 gr/cm3 density, 6.5-7 Mohs hardness, refraction index equal to 1.73-1.76; massive bicolour pink and green sample of Hydrogrossular are known such as Chromogrossular of a bright green colour due to Chrome, red-orange Essonite, green Tsavorite (containing Vanadium and Chrome).
