The Science and Legends of Birthstones

Garnet can be found in metamorphic rocks and sometimes in granites and volcanic rocks.

Amethyst is popular for its color and crystal shapes that produce handsome, purple, sparkling clusters. 

Aquamarine is a variety of the mineral beryl. Beryl generally forms inside granites as magma (molten rock) cools deep inside the Earth.

Diamond is a form of carbon with a tightly bound crystalline structure that originates deep inside the Earth.

Emerald is another variety of beryl. It is surprisingly common for emeralds to contain flaws and veins of chemicals called inclusions.

When light enters the stone, it is bounced back and forth between these layers before it exits as the glowing moon-like effect we see.

Ruby originates from metamorphic rock, and is a variety of the mineral corundum, second only to the diamond in hardness.

Peridot is type of olivine, and comes in various shades of green, from light to a brilliant olive green.

Sapphire is any form of corundum that is not red, as red varieties are called rubies.

The presence of water in the mineral structure allows geologists to determine the temperature of the rock at the time the opal formed.

Some citrine actually began as purple amethyst, but heat from nearby molten rock changed it to a warm yellow color.

Turquoise is composed of hydrated copper and aluminum phosphate. It forms when circulating water alters other aluminum-rich rocks in desert environments.