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Prehnite - Ca2Al2Si3O10(OH)2

Prehnite -

Mineral Profile

Australian Prehnite

Sorry, we don't have a card for this crystal yet!

Please enjoy the information anyway -

Grades: There are many different qualities to Prehnite which make a large fluctuation on the value of the stone. Facetable pieces are of the highest rareness and value; These pieces are completely transparent and are considered precious stones. Rarity isn't the only factor that can cause a gemstone to be high priced (for example Diamonds, there are millions of those and they are regarded high priced). The colour, transparency, durability and beauty are the true attributes of high value "gem material".

Colours: Green, Yellow, White, Grey

Luster: Vitreous, Pearly - Translucent

Rarity: Although Prenite can be sourced around the world it is considered a rare, semi-precious (sometimes precious) and often expensive stone.

Country of Origin: There are multiple localities worldwide that product Prehnite; South Africa, Namibia, France, Austria, Germany, Italy, Scotland, Switzerland, UDS, Canada, India, China, Antarctica and Australia!

In Australia Prehnite is sourced from many deposits across Australia. New South Wales; Localities such as Coonabarabran, The Warrumbungle mountain range, Emu Quarry, Broken hill and Prospect hill; Northern territory in areas such as Wave Hill and Western Australia in deposits in the Kimberly.

Hardness: 6 - 6½ - Prehnite has a hardness of 6 - 6.5 and fractures unevenly. It is a fairly soft gemstone that can be scratched easily by any harder gemstone.

Once polished into a Cabochon for jewellery Prehnite is perfectly hardy to be worn as rings, necklaces, earrings and more.

Chemical Composition: Ca2Al2Si3O10(OH)2 - Hydrated Calcium Aluminum silicate

Crystal system: Orthorhombic - (3 Dimensional geometrical arrangements having three unequal axes at right angles)

Growth: Uncommon crystals (blocky to thin tabular); aggregates are fanlike, reniform, globular, stalactitic, granular, compact.

History: Prehnite was named in honour of Dutch Colonet Hendrik Von Prehn in 1733, after its original discovery in the Cape of Good Hope Colony, South Africa. It is claimed by some historians, that Prehnite was the first mineral to be named after a person.

Rising Value: Due to the diminishing amount of Jade on the market, (Jade is another precious green coloured stone, with cultural significance to Chinese cultures), there is lots of foreign interest in purchasing high quality Australian Prehnite or prehnite mines to act as a Jade substitute in the market. In China, the colour green is associated with purity and moral integrity; they have a saying - Gold has value but Jade is invaluable. Prehnite is sometimes sold as "Grape Jade" due to its botryoidal forms and similar colour. There has been major chinese investment into Australian Prehnite mines, renaming the stone "Sun Jade" or "Sun Jewels".

Health Information: Extreme care should always be taken if cutting or performing lapidary work on gemstones. There is no posed health risk of handling Prehnite.

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