This is a 4 cm long sapphire crystal from Mysore district, Karnataka, India.
The blue color of Corrundum is Sapphire. This one measures 39x20x19 mm, and it is 30 grams.
The crystal shape is natural hexagonal (6 sided), and the top is polished.
The 3 last picutures is with normal daylight, while the other pictures are with extra light to highlight it's beautiful purple color.
If you are interessted of buying more than 1 peice, please contact me. The price for $12 is for the exact crystal you see on the pictures (the price on the others can be a little different, depending on size and quality).