ivory and bones cleansing - Ivory and Bones cleansing; ivory and bones cleansing -
Spirits of turpentine is very efficacious in removing the disagreeable colour and fatty emanations of bones or ivory, while it leaves them beautifully bleached. The articles should be exposed in the fluid for 3 or 4 days in the sun, or a little longer if in the shade. They should rest upon strips of zinc, so as to be a fraction of an inch above the bottom of the glass vessel employed. The turpentine acts as an oxidising agent, and the product of the combustion is an acid liquor which sinks to the bottom, and strongly attacks the ivory, if allowed to touch it.
Make a thick puddle of common whiting in a saucer. Brush well with a tooth-brush into the carved work. Brush well out with plenty of clean water. Dry gently near the fire. Finish with a clean dry hard brush, adding one or two drops (not more) of sweet oil.
Mix about a tablespoonful of oxalic acid in ½ pint of boiling water. Wet the ivory over first with water, then with a tooth-brush apply the acid, doing one side at a time, and rinsing; finally drying it in a cloth before the fire, but not too close.
Take a piece of fresh lime, slake it by sprinkling it with water, then mix into a paste, which apply by means of a soft brush, brushing well into the interstices of the carving; next set by in a warm place till perfectly dry, after which take another soft brush and remove the lime. Should it still remain discoloured, repeat the process, but be careful neither to make it too wet nor too hot in drying off, or the article may come to pieces, if glued or cemented together. If it would stand steeping in lime-water for 24 hours, and afterwards boiling in strong alum-water for about an hour and then dried, it would turn out white and clean. Rubbing with oxide of tin (putty powder) and a chamois leather, will restore a fine gloss afterwards.
Well clean with spirits of wine, then mix some whiting with a little of the spirits, to form a paste, and well brush with it. It is best to use a rubber of soft leather where there are no delicate points; put a little soap on the leather, and dip into the paste, and rub the ivory until you get a brilliant polish, finish off with a little dry whiting; the leather should be attached to a flat wood surface, and rub briskly.
When ivory ornaments get yellow or dusky-looking, wash them well in soap and water, with a small brush to clean the carvings, and place them while wet in full sunshine under a glass cover; wet them two or three times a day for several days, with soapy water, still keeping them in the sun; then wash them again, and they will be beautifully white. The glass cover is essential as without it the surface will be covered with fine cracks. To bleach ivory, immerse it for a short time in water containing a little sulphurous acid, chloride of lime, or chlorine.