Turquoise is an opaque, blue-to-green mineral that is a hydrated phosphate of copper and aluminium. The word turquoise dates to the 17th century and is derived from the French turquois for "Turkish" because the mineral was first brought to Europe through Turkey. Turquoise is rated between 5 and 6 on the Mohs hardness scale. Turquoise is associated with fate. Turquoise is thought to harmonize and protect and help to recognize causes of emotions.