I'm unsure of whether the developers known about the Hemerdon Tungsten and Tine Mine. Deposits were found in the 1860s and in WWI due to a shortage of tungsten a mine was sunk in 1917 and was operational in 1918. The deposits were expensive to pull out of the ground and it closed in the 1930s but opened in 1939 and in 1944 was closed down. It was opened again in 2014 because the price of tungsten ore went though the roof.(Although not as much as Silver Thursday. When the price of silver increased by over 700%)
https://en.wikipedia.org/wiki/Drakelands_Mine#1867.E2.80.931959
http://www.wolfminerals.com.au/irm/content/drakelands-mine.aspx?RID=324&RedirectCount=1
https://en.wikipedia.org/wiki/Drakelands_Mine#1867.E2.80.931959
http://www.wolfminerals.com.au/irm/content/drakelands-mine.aspx?RID=324&RedirectCount=1
- 8