The small rough crystals of blue Sapphire are about 1 - 2cm in size.
Per VE (=packing unit) with 100g you get about 20 to 25 rough sapphire stones.
Strengthening of mental power and perspicacity are the classical topics, where blue Sapphires are used aufgund their effect. The mineral can lead to an unshakable inner peace.
Sapphire is blue corundum.