This name refers to three monomineral stones (jade, jadeite and nephrite) used in jewellery. With its colour ranging from a pale green to dark green, jade (from the Chinese "Yü") is mainly composed of tremolite crystals. This metamorphic rock is found in some shists and serpentines.

Its name originates from the Spanish "piedra de la ijada" (side stone) as people believed it could cure renal colic.