Important placers formed in marble environments are found in Myanmar, where gembearing levels enriched in pebbles, sand, silt, clay, and iron oxides are called "byon" (Kane and Kammerling, 1992). The gem content is closely related to the formation of karst and chemical weathering of marble and associated rocks.
Oct 09, 2016· Nigeria – Central Nigeria is a source of reddish purple tourmaline. Kenya – Tourmaline in greens and yellows is mined in Kenya. Tanzania – The Umba Valley in Tanzania is known as an important source of many fine gemstones including tourmaline. Namibia – Namibia is a source of finequality gem tourmaline including unique bluegreen stones.
can be found in brown, orange, pink and brownishred. The first deposits of orange spessartite were found in Germany in the 1990s. Spessartite garnet is currently mined in Nigeria, Ramona (California) and Namibia. One will often hear the gem trade name of Mandarin, malaia or tangerine used to refer to the best of this popular garnet.
Small deposits of Tourmaline of similar color to Paraiba Tourmaline were also recently found in Nigeria and Mozambique, and these are often also called "Paraiba Tourmaline" in the gem trade. Other valuable forms of Tourmaline are Chrome Tourmaline, an intensegreen Tourmaline found in Tanzania, Rubellite, the pink to red variety, and Indicolite, the rare blue variety.
Nov 05, 2006· The national gemstone of Iran is turquoise, which is a blue green gem of that is rarely a single colour. Obviously, since it is their national gemstone, turquoise is found in Iran and has been mined there for millions of years. There are many different gemstones out there for every country in the world,...
Gemstones found in igneous rock include the quartzes (including amethyst, citrine and ametrine), the garnets, moonstone, apatite, diamond, spinel, tanzanite, tourmaline, topaz and zircon. Some of these gemstones form in pegmatites and hydrothermal veins that are genetically related to igneous rocks.
Many minerals form beautiful crystals, but the most prized of all are gemstones. Uncut gems often look fairly ordinary–like rocks. It's only when they are cut and polished that they obtain the brilliance and luster that gives them their value. Historically, gems have been divided into precious and semiprecious classes.
Aug 22, 2014· The recent arrival of highquality blue sapphire from a new source in Africa has caused considerable excitement in the Bangkok marketplace. These gems, reportedly from the Mambilla Plateau in Nigeria's Taraba State, are available in large rough sizes, some as big as 100–300 ct.
Oct 26, 2012· Gemstones 1. Shaumik Daityari GLT, 2nd year 2. GemstoneA gemstone or gem (also called a precious or semiprecious stone, a fine gem, or jewel) is a piece ofmineral, which, in cut and polished form, is used tomake jewellery or other other materials (like amber) which are notminerals, used to make jewellery, are also calledgemstones.
Beryl forms some of the most wellknown and prized gemstones. The deep green variety Emerald is one of the most valuable gems. Aquamarine, a semiprecious gem, is the most popular light blue gem. Morganite, Golden Beryl, and Heliodor are also used as gems, though Goshenite and Red Beryl are less frequently faceted into gemstone cuts.
Gemstones Deposits in Nigeria with their Locations and Uses. Gemstones in Nigeria alone can sustain the country for years, but because of the distraction of crude oil, the places with gemstones deposit have been left to be mined illegally and unguided without minding .
Aquamarine is a gemstone found in Brazil, India, Nigeria, Pakistan, Russia, and The United States. In the United States, Aquamarine can be found in Colorado, Maine, North Carolina, and Vermont. Diamonds are scarcer in the United States, and in other countries, which attributes to their high value.
It also forms from chemical reaction in fluids. One can find garnet deposits throughout the world, in the United States, Brazil, Germany, the Czech Republic, Austria, Kenya, Madagascar, Tanzania, Russia, Pakistan, Sri Lanka, China and India. Any of these formations can include gemstone quality garnets along with lesser quality material.
These gemstones are most commonly found in Nigeria, though varieties can also be found in Namibia and Zimbabwe. There are different colors of topaz, but the varieties from Africa are typically yellow, golden brown, and varying shades of blue.
These Tourmalines showed intense pink coloring, sometimes bordering on red "Rubellite" hues. This gem is a good example of how much fire and intensity these Nigerian Tourmalines can pack into a smaller sized stone. Even though this gem is less than 1 carat in weight, it's about as saturated as they come.