https://www.ausimm.com/publications/conference-proceedings/the-ausimm-proceedings-1950/the-valuation-of-auriferous-alluvial-deposits-by-the-use-of-a-keystone-drill/
The Valuation of Auriferous Alluvial Deposits by the Use of a Keystone Drill
It is difficult, and probably inadvisable, to frame rigid rules for the valuation of alluvial deposits, for such deposits are very diverse in type, varying,...
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