The last professional attempt at mining finished in 1960 with...

The last professional attempt at mining finished in 1960 with (GMA) Mines Ltd in the previous 5 years there had been 6800 feet of development and 8600 feet of drilling on the reefs between the 19 and 24 levels but only exposed a few minor ore bodies based on what Lindesay Clark has stated - but then what would a guy with his background know -sarcasm .
Looks to me they stopped mining because they could not find any decent high grade ore .
"There was no encouragement from one deep hole which was drilled to the 30 level"