This ruby in mavinite is from Mavinhalli in the Mysore District of Karnataka, India. Mavinhalli is the type locale for mavinite which is a brittle green mica containing the elements Mg, Fe, Al, Si, O and H. The mavinite partially encases the ruby which is the red variety of corundum. Corundum is an oxide mineral containing the elements Al and O. The red coloring is from trace amounts of chromium in the crystal matrix. It has richer red color than most crystals from Mysore. This piece measures 1 5/8 x 1 1/2 x 5/8 inches or 41 x 38 x 16 mm.