The birthstones for October are tourmaline and opal. Tourmaline comes in various colors like black, brown, violet, green, and pink. It is a semi-precious gemstone that is mined in countries like Brazil, Tanzania, and the United States. Opal is known as the "Queen of Gems" and comes in colors like white, yellow, red, orange, green, brown, black, blue, and colorless. It is mostly mined in Australia, though also found in other countries. Both stones were thought in folklore to have various powers and were used in traditions.