Monday, 29 June 2015

Tanzanite

Tanzanite is the blue/purple variety of the mineral zoisite. (a calcium aluminium hydroxy silicate) It was discovered in the Mererani Hills of Manyara Region in Northern Tanzania in 1967, near the city of Arusha and Mount Kilimanjaro.

This is the only known source in the world and it has been depleted over the years. Naturally-formed tanzanite is extremely rare.
Tanzanite is noted for its remarkably strong trichroism, appearing alternately sapphire blue, violet and burgundy depending on crystal orientation. Tanzanite can also appear differently when viewed under alternate lighting conditions. The blues appear more evident when subjected to fluorescent light and the violet hues can be seen readily when viewed under incandescent light.


TanzaniteOne Mining Ltd. is a gemstone mining company which exclusively mines the blue gemstone.

TanzaniteOne Mining Ltd is a fully owned subsidiary of the London AIM listed resource company, Richland Resources.( AIM : RLD )
Tanzanite is a relatively new gemstone in the world of gemology and jewelry. Since its discovery, tanzanite has sold for as little as $20 per carat and as much as $1,000 per carat or more, for gem-quality, finely coloured stones.

That price may seem like a bargain in time, as tanzanite is a single-source gemstone and that source is expected to be mined out within the next 20 to 30 years based on the latest mining information.
Tanzanites are typically blue or violet-blue, but they can also be rare greenish and greenish-blue shades.

Vanadium is the main coloring agent required to produce the rich blue-violet colors that are so highly prized.

Tanzanite is like all other gems in that small stones are more abundant than larger stones. Most faceted tanzanites are under five carats in weight. Stones over fifty carats are extremely rare.


See ----->http://pennystockjournal.blogspot.ca/2014/06/tanzanite-101.html

Sunday, 28 June 2015

Argentine police arrest 'meteorite thieves'

Police in Argentina have arrested four men who appear to have been trying to steal more than a tonne of meteorites in the northern province of Chaco. Highway police say they found more than 200 large pieces of meteorites hidden under the seats of a truck which they had stopped in a random check. Three Argentines and a Paraguayan were arrested.

The province of Chaco is world famous for meteorites, which are protected under Argentine law.
A 37-ton space rock crashed to Earth as part of a meteor shower between 4,000 and 5,000 years ago, forming a giant 1,300 sq km (500 sq miles) kilometer crater field in northeastern Argentina known as Campo del Cielo, or Field of the Sky.

Named El Chaco after the province it fell into, the meteorite is central to the native Moqoit people.
El Chaco was discovered with a metal detector in 1967. It is the second-biggest meteorite ever found.

In 1990 an Argentine highway police officer foiled a plot to steal it for sale to a private US collector.
Campo del Cielo meteorite is classified in Group I, , 6.68% Ni, 0.43% Co, 0.25% P, 87 ppm Ga, 407 ppm Ge, 3.6 ppm Ir.

Almost all of the remaining portion of the meteorite is iron.

"Las Víboras" fragment found in Campo del Cielo

Campo del Cielo meteorite, El Chaco fragment

:Campo del Cielo meteorite, El Chaco fragment



See ----->http://pennystockjournal.blogspot.com/2014/06/gems-from-space.html




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Saturday, 27 June 2015

Gems of Luc Yen, Vietnam

In 1987, gems were discovered in the Luc Yen area of Vietnam’s Yen Bai province. Ruby, sapphire, and spinel from primary and secondary deposits are the most valuable. Tourmaline, gem-quality feldspar, pargasite, and humite are also mined there.

As a result of this discovery, the Luc Yen district has become Vietnam’s most important gemstone-trading center over the past 30 years. The Luc Yen district mainly consists of jungle-covered karsts separated by several narrow valleys where paddy fields and traditional villages are located.
It is bordered on the west, south, and east by Thac Ba Lake. The lake was created in 1970 by the construction of a dam for Vietnam’s first hydroelectric power plant. Thac Ba Lake is 80 km long and contains more than a thousand islands.
Covering the area between Tan Huong and the Luc Yen peninsula, it submerged a gem-rich area.

Cluster of red spinel octahedrons on the marble-host from Luc Yen, Vietnam
Vietnamese spinel was initially found at Luc Yen but today, Yen Bai is the only active source. The newest deposit, found in February 2010, is Lang Chap, notable for its orange-red padparadscha-like stones. The most productive spinel deposit remains the old Cong Troi mine in An Phu, which yields a wide range of colours.
A local gem market is held in the town of Luc Yen every morning at 8 o'clock, where local production of gems and minerals is available for sale.