Siilver ingots which have been melted by unknown refiners or in the old native furnace are only accepted by the Mint after they have been properly melted in the Melting Department and cast into the form of Mint refined ingots under the superintendence of the assayer. Silver ingots which have been melted in the Mint refinery, or by known European Melters do not require to be thus melted.
From off each individual ingot an assay piece is then cut in the presence of the assayer, and this piece is assayed by him personally. The fineness of each ingot as determined by him is reported to the Commissioner, and from this fineness the amount of alloy (copper) required by each, to yield bars of standard fineness, is calculated by the chief Japanese officers of the Assay Department and of the Melting Department. Each ingot with its accompanying copper is then placed in a plumbago crucible, melted and thoroughly mixed by stirring; a small quantity of the molten metal is then carefully taken out from each crucible, quenched in water and wrapped cash in its separate assay paper. These operations are performed under the superintendence of the assayer.
This "dip assay piece" from each crucible of metal is then assayed at once by ...
Dec.