Dictionarium polygraphicum. Calamine stone, lapis calaminaris, calamite, cadmia.

Dictionarium Polygraphicum:
Or, The Whole Body of Arts Regularly Digested.
Vol I.
London: Printed for C. Hitch and C. Davis in Pater-noster Row, and S. Austen in St. Paul's Church Yard. MDCCXXXV.
Calamine stone, lapis calaminaris, calamite, cadmia - a kind of fossil bituminous earth much us'd in foundery; being us'd in tinging copper of a yellow colour, i.e. in converting it into brass.

It is either of a greyish colour, as that of Germany and England; or reddish, as that about Leige, and in some parts of France, accounted the best, because yellow by calcination.

It is dug out of mines, usually in small pieces, having eyes, sometimes veins, of lead usually; tho’ not always found in lead mines.

It is generally dug in barren rocky ground; its courses running usually at fix a clock (as the miners phrase it) i. e. from east to west, sometimes at nine and sometimes at twelve; or per pendicular, which is accounted the best.

After it has been dug, it is wash'd, or buddled (as they term it) in a running water, which carries off the impurities and earthy parts, leaving the lead, calamine, and other sparry parts at the bottom; then it is put into a sieve, and shaken well in water, and the lead that is mixt with it sinks to the bottom, the sparry parts ascend to the top, and the calamine remains in the middle.

Having been thus prepar'd, they bake it in an oven for four or five hours, the flame being so contriv'd as to pass over, and so to heat and bake the calamine; it is kept continually stirred and turned with an iron rake.

This being done, it is pounded to a powder, and all the stones found in it are picked out, and then it is fit for use.

As to the manner of applying it in the preparation of brass, see the article BRASS. And for other uses, other articles.

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