Mining in focus
The greenish colour is an indication of high-grade cassiterite.
New regulations and environmental legislation have put pressure on the output of tin ore and will see the price of refined tin increase in the next couple of years. Today, tin is used in transparent circuit boards and as a solder in electronic devices. Niobium-tin alloy is used for superconducting magnets. The more traditional application is to coat other metals to prevent corrosion, such as in tin cans. Tin is also used in soft solder, pewter, bronze, and phosphor bronze.
Researchers at Stanford University and the Department of Energy’ s SLAC National Accelerator Laboratory in the USA, have invented a one-atom-thick layer of tin called Stanene. Stanene is the first material able to conduct electricity with 100 % efficiency at room temperature. The addition of a few fluorine atoms maintains this efficiency up to and beyond the temperatures at which computer chips operate.
After the recent surge in tin prices to about USD20 800 a tonne from USD13 350 a tonne in January 2016, companies are also looking at previously unviable deposits. Tin prices have ranged widely, reaching as high as USD33 000 a tonne in 2011.
Geological setting
Cassiterite is considered to be the only economically significant tin mineral in the earth’ s crust, and in its purest form has a tin content of 78.6 %. Cassiterite is mainly found in quartz-pegmatite veins, along with a number of other minerals. The pegmatite veins are usually associated with evolved granitic host rocks. There is particular interest in pegmatite deposits that host both tin and lithium mineralisation.
Underpinning surging tin prices are a shortage of new mines and European Union legislation( enacted in 2006) requiring lead solder to be phased out in electronics. The solder has been substituted with a mix of which 95 % is tin. The other development was the passing of the Dodd-Frank Act in the USA, which contains provisions to prevent four key minerals( tin, tantalum, tungsten, and gold) mined in the Great
Lakes region in Africa from being used to finance armed conflicts. Now smelters can buy tin only from certificated sources.
Near-future tin demand
According to BMI Research, a division of Business Monitor International, the global tin market is expected to move into a deficit from 2018 onwards, pushing prices higher. It is expected that inventories will be further depressed by heightened demand and slowing global production growth. The report further forecast that the tin market will shift from a surplus of 400 tons( t) in 2017 to a deficit of 3 500t in 2018 and by 2021, the deficit is forecast to deepen to 12 600t. Based on these projections, the price of tin is expected to increase from an average of USD20 500 per ton in 2018 to USD22 500 per ton by 2021.
One of the main reasons for the drop in tin output is China’ s stricter environmental regulations. The refined tin market is also expected to decline as Indonesia’ s production is expected to drop off. At the same time, the world demand
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