Tiger’s eye (also called tiger eye) is a chatoyant gemstone that is usually a metamorphic rock with a golden to red-brown color and a silky luster. As members of the quartz group, tiger’s eye and the related blue-colored mineral hawk’s eye gain their silky, lustrous appearance from the parallel inter-growth of quartz crystals and altered amphibole fibres that have mostly turned into limonite.
Tiger iron is an altered rock composed chiefly of tiger’s eye, red jasper and black hematite. The undulating, contrasting bands of color and luster make for an attractive motif and it is mainly used for jewelry-making and ornamentation. Tiger iron is a popular ornamental material used in a variety of applications, from beads to knife hilts.
Tiger iron is mined primarily in South Africa and Western Australia. Tiger’s eye is composed chiefly of silicon dioxide (SiO2) and is colored mainly by iron oxide. The specific gravity ranges from 2.64 to 2.71.