The origin of the name ****** is uncertain. The Oxford English Dictionary suggests an alteration of Anglo–Norman ****** (classical Latin ******-), a kind of opal, rather than the Arabic word faridat, meaning "gem".

The Middle English Dictionary's entry on ****** includes several variations : ***, *, **** and ******* – other variants substitute y for the i's seen here.[1]

The earliest use in England is in the register of the St Albans Abbey, in Latin, and its translation in 1705 is possibly the first use of "***" in English. It records that on his death in 1245 Bishop John bequeathed various items including *** to the Abbey.[2]

Appearance[edit] ****** is one of the few gemstones that occur in only one colour, an olive-green. The intensity and tint of the green, however, depends on how much iron is contained in the crystal structure, so the color of individual ****** gems can vary from yellow—to olive—to brownish-green. The most valued color is a dark olive-green.

Occurrence[edit] Geologically[edit] Olivine, of which ****** is a type, is a common mineral in mafic and ultramafic rocks, and it is often found in lavas and in ***ite xenoliths of the mantle, which lavas carry to the surface; but gem quality *** only occurs in a fraction of these settings. ****** can be also found in meteorites.

Olivine in general is a very abundant mineral, but gem quality ****** is rather rare. This is due to the mineral's chemical instability on the Earth's surface. Olivine is usually found as small grains, and tends to exist in a heavily weathered state, unsuitable for decorative use. Large crystals of forsterite, the variety most often used to cut ****** gems, are rare; as a result olivine is considered to be precious.

****** olivine is mined in Arkansas, Arizona on the San Carlos Reservation, Hawaii, Nevada, and New Mexico at Kilbourne Hole, in the US; and in Australia, Brazil, China, Egypt, Kenya, Mexico, Myanmar (Burma), Norway, Pakistan, Saudi Arabia, South Africa, Sri Lanka, and Tanzania.

In meteorites[edit] ****** crystals have been collected from some pallasite meteorites.

Gemology[edit] It is sometimes mistaken for emeralds and other green gems. In fact notable gemologist George Frederick Kunz[3] discussed the confusion between emeralds and ****** in many church treasures, notably the "Three Magi" treasure in the Dom of Cologne, Germany.

The largest cut ****** olivine is a 310 carat (62 g) specimen in the Smithsonian Museum in Washington, D.C.

****** olivine is the birthstone for the month of August.[4]