Check the listing for details. prehnite necklace. Listed at 45.00 USD. prehnite necklace. Shipped with USPS First Class. Prehnite History Prehnite was officially named in 1788 after a Dutch colonel named Hendrik von (or van) Prehn. Prehn--a naturalist and mineral collector--was given credit for discovering the stone in 1774, at the Cape of Good Hope in modern South Africa. This stone has been given a number of other names over the years, including adelite, chiltonite, chrysolite of sage, coupholite, Karoo stone, grape jade and more. Prehnite Metaphysical Properties Prehnite is considered a "stone of dreaming"; it is believed to increase the power of the dream state, strengthen lucid dreaming and promote communication with other planes of existence. It is also considered a "stone of prophecy," with long use by indigenous peoples of South Africa. Although not a birthstone, prehnite is affiliated with the zodiac sign Libra. It is often associated with the third eye chakra. Prehnite Geological Properties Prehnite forms in the veins and cavities of volcanic rock, often basalts, but also occurring in granites. This stone is usually translucent, yet rarely transparent or clear. Cat's eye formations within prehnite are possible, but rare. It is a rather singular gemstone, with no near relatives, although many are visually similar enough to cause confusion. Prehnite has been mistaken for jade, serpentine, chrysoprase and other stones. Prehnite can be found in South Africa, Australia, Canada, Mali, Morocco, Namibia and a variety of small deposits across Europe and the United States. A distinctive pink variety is found among the basalt deposits in the US state of Michigan, on the Keweenaw Peninsula, containing copper and chlorite inclusions. Mineral Information Calcium alumosilicate Chemical Composition Ca2Al2Si3O10(OH)2 Color Usually muted yellow-green; also colorless, gray, yellow, white, pink, orange, blue Hardness 6 to 6-1/2 (Mohs) Specific Gravity 2.8 - 2.95 Refractive Index 1.611 - 1.669