Labradorite exhibits a play of colours.

     Adularia is a transparent to sub-transparent variety of orthoclase and is used as a semi-precious stone. It is a very low temperature potassium feldspar.

     Orthoclase is a silicate of aluminium and potassium crystallising in the monoclinic system. It is usually white, grey, pale yellow or flesh-red in colour and its streak is uncoloured. It's specific gravity is between 2.57 and 2.58.

      Orthoclase is used in the manufacture of  porcelain. It is one of the important feldspar group of minerals.

     Amazonstone is the bright or pale green  variety of microcline. It is used as a semi-precious stone.

   Beryl is a silicate of aluminium and beryllium crystallising in the hexagonal system. Crystals are common. Its hardness varies from 7.5 to 8 and the specific gravity ranges from 2.63 to 2.8. The colour of beryl is usually green, blue, white or pink. Its streak is white. Lustre varies from vitreous to resinous and the fracture is concoidal to uneven.

   A green hexagonal crystal of beryl from Nellore, Andhra Pradesh is exhibited in the gallery.

   Like orthoclase, microcline is also used in the manufacture of porcelain. It is one of the important feldspar group of minerals.