Search results
Results from the WOW.Com Content Network
The niobium-dominant mineral in coltan is columbite (after niobium's original American name columbium), and the tantalum-dominant mineral is tantalite. [1] Tantalum from coltan is used to manufacture tantalum capacitors which are used for mobile phones, personal computers, automotive electronics, and cameras. [2]
Dating columbite minerals is primarily completed by uranium lead (U-Pb) dating, a slow process. Columbite has the same composition and crystal symmetry (orthorhombic) as tantalite. [6] In fact, the two are often grouped together as a semi-singular mineral series called columbite-tantalite or coltan in many mineral guides
Coltan is the colloquial name for the mineral columbite-tantalum ("col-tan"). In the early 21st century coltan mining is associated with human rights violations such as child labour, systematic exploitation of the population by governments or militant groups, exposure to toxic chemicals and other hazards as a result of lax environmental protection, and general safety laws and regulations. [1]
The mineral group tantalite [(Fe, Mn)Ta 2 O 6] is the primary source of the chemical element tantalum, a corrosion (heat and acid) resistant metal.It is chemically similar to columbite, and the two are often grouped together as a semi-singular mineral called coltan or "columbite-tantalite" in many mineral guides.
This is a list of prices of chemical elements.Listed here are mainly average market prices for bulk trade of commodities. Data on elements' abundance in Earth's crust is added for comparison.
Coltan is the most profitable mineral export from the Congo, but it is particularly difficult to track because it is often listed as cassiterite, for which export taxes are lower. Coltan had been illegally extracted and sold via Burundi since 1995, three years before the invasion began. [58]
The University of California Santa Barbara published a study in 2010 on the subject called, "Economics of Cell Phone Reuse and Recycling" that states the value of reused and recycled cell phones. In 2006, according to the study the average cost for U.S. cell phone refurbishers ReCellular , PaceButler and RMS was $2.10 while the average revenue ...
Artisanal gold mines near Dodoma, Tanzania. Makeshift sails lead fresh air underground. Artisanal and small-scale mining (ASM) is a blanket term for a type of subsistence mining involving a miner who may or may not be officially employed by a mining company but works independently, mining minerals using their own resources, usually by hand.