Sapphire is the birthstone for those born in September. It symbolizes truth, sincerity and loyalty. It is also thought to bring peace, joy and wisdom to its wearer. The sapphire was also believed to be a talisman that would protect against evil spirts. Sapphire is a gem quality variety of the mineral corundum. It is the 2nd hardest substance on earth after diamond, rating 9 on the Mohs scale of mineral hardness. Blue is indeed the best known and the most valuable of sapphire colors.