The delusion was abetted by unscrupulous assayers, and by swindlers selling secret metallurgical processes to extract gold from the shale.
He was appointed as a member of a royal commission on collieries in 1886 and worked as a mining captain and assayer in 1890.
Some minor modifications were subsequently made in the location of the mintmark and assayer's initials.
The case was over the role of assayers when acting as brokers between mine vendors and mine purchasers.
After he had completed his courses there in 1820 he obtained employment, chiefly as an assayer, in connexion with the royal mines and metal works.
They are trials in the full judicial sense, presided over by a judge with an expert jury of assayers.
Exhibitions include a replica of a mining tunnel and an assayer's office, both which visitors walk through.
Within five years new brokers, assayers and refiners opened.
