Manufacturing Carmine.

Manufacturer and builder (11 / 1871)

[236] MANUFACTURING CARMINE. - You will find that there is some reason why carmine commands a high price, as it can not be made cheap. Here is the recipe you ask: Take 2 ounces of cochineal, rub it fine and boil in a tinned copper vessel for half an hour with 5 gallons of rain-water, to which you previously add 2 scruples of Roman alum. Let the solution stand for fifteen minutes, filter through a clean piece of flannel, the drop in a saturated solution of tin in aqua regia, as long as any thing precipitates; then stir it all up with a wooden spoon, and let it rest for 48 hours in an earthen vessel, when the carmine will be found as a layer on the bottom; then pour off the water and wash the residue with rain-water several times; every time let it settle and pour off again, then dry the carmine between blotting-paper or on flat dishes. You can not be too careful in regard to the cleanliness of your vessels and tools, the purity of the water, and the avoidance of dust, in order to obtain a beautiful bright article. The tin solution mentioned is identical to the tin mordant mentioned on page 216, answer to query 201, where the word "tin" was omitted at the end, so as t o read "two drachms of grain tin" or "granulated tin".

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