Moonstone is a mineral from the feldspar group that displays a pearly and opalescent play of color caused by light diffraction within its crystal structure.
Moonstone has been used in jewelry for millennia, including ancient civilizations such as the Romans, who admired it because they believed it was born from solidified rays of the Moon. Carvings of the moon became very popular, like the brooch picture below, from 1888.
Moonstones also had a powerful connection with pagan cultures, especially in clairvoyance and shamanism. It also accrued meaning in relationship to love, and believed to be an aphrodisiac, and when worn by two people, it will help them fall in love or repair any relationship issues. Moonstone is still a very highly prized gemstone nowadays and the birthstone of the month of June.
The piece below is from the 7th century.
Deposits of Moonstone occur in Armenia, Australia, Austria, Mexico, Madagascar, Norway, Poland, India, Sri Lanka and the United States. From the late 1880s to the early 1920s small Moonstone specimens gave its name to Moonstone Beach, a beach community of Redondo Beach, California where visitors day-tripping from Los Angeles as well as tourists from the East Coast gathered the moonstones from the many mounds of gemstones washed ashore.