Mining News - In 2014-2015 Russia exported 21 tons of tungsten scrap at $3.6 per kg, while in 2016 – 138 tons at $10.8 per kg and in 2017 it is expected that exports will reach 70 tons at $13 per kg.
The duty imposition is explained by the shortage of tungsten raw materials on the local market.
http://www.miningnewspro.com/en/News/72689/Russia: tungsten scrap exports to be limited