Turquoise is an opaque, blue-to-green mineral that is a hydrated phosphate of copper and aluminum. It is rare and valuable in finer grades and has been prized as a gemstone and ornamental stone for thousands of years owing to its unique hue.
The gemstone has been known by many names. Pliny the Elder referred to the mineral as Callais (from Ancient Greek κάλαϊς) and the Aztecs knew it as chalchihuitl. 

Jade or “yu” (meaning precious stone) as it is called in China, is the family name for Jadeite and Nephrite. The name nephrite is derived from lapis nephriticus, which in turn is derived from Greek λίθος νεφριτικός; νεφρός λίθος, which means 'kidney stone' and is the Latin and Greek version of the Spanish piedra de ijada (the origin of "jade" and "jadeite"). Accordingly, nephrite jade was once believed to be a cure for kidney stones.