cupelling

I burned and crushed bones to make my bone-dust for cupelling, and thus provided made nearly forty assays, some of which were afterwards checked in Adelaide, in each instance coming as close as check assays generally do.

Getting Gold: a practical treatise for prospectors, miners and students

The muffle used for this purpose must not be used at the same time for cupelling; a gas muffle (fig. 22), such as one of Fletcher's, is best.

A Text-book of Assaying: For the Use of Those Connected with Mines. Cornelius Beringer 1886

~ -- The silver is best separated in the wet way before cupelling, but if the proportion is not too small, it can be found by cupellation.

A Text-book of Assaying: For the Use of Those Connected with Mines. Cornelius Beringer 1886

The cupel is necessarily porous, and particles of metal may perhaps drain into it, more especially if the bone ash is not in fine powder; but if this is the main source of loss it is hard to see why, in cupelling equal weights of silver and gold, the loss is not equal in each case.

A Text-book of Assaying: For the Use of Those Connected with Mines. Cornelius Beringer 1886

-- Gold, obtained by cupelling and "parting," is for most purposes sufficiently pure.

A Text-book of Assaying: For the Use of Those Connected with Mines. Cornelius Beringer 1886

If the button left on cupelling the lead from an assay of an ore appears white, it is best to assume that it already contains at least a sufficiency of silver, in the absence of any knowledge to the contrary.

A Text-book of Assaying: For the Use of Those Connected with Mines. Cornelius Beringer 1886

Make a preliminary assay by cupelling 0.1 gram of the alloy with 1 gram of assay lead; calculate the percentage composition.

A Text-book of Assaying: For the Use of Those Connected with Mines. Cornelius Beringer 1886

The determination may also be made by cupelling the button of lead got in the dry lead assay.

A Text-book of Assaying: For the Use of Those Connected with Mines. Cornelius Beringer 1886

The alloy left after cupelling was made up of 1 part of gold to

A Text-book of Assaying: For the Use of Those Connected with Mines. Cornelius Beringer 1886

Refer to the table on page 105 to find what weight of lead is required for cupelling

A Text-book of Assaying: For the Use of Those Connected with Mines. Cornelius Beringer 1886