264 IVORY AND THE ELEPHANT 



still are made, to impart various colours to the material, 

 and we shall here note a few of the processes employed 

 for this purpose.* 



A yellow hue may be secured by using as a stain GO parts 

 of finely ground curcuma root, which has been digested 

 for a day in 500 parts of 80 per cent, alcohol, and then filtered 

 through blotting paper. Another yellow stain is com- 

 posed of 95 parts of aniline yellow dissolved in 750 parts of 

 80 per cent, alcohol; this solution is also to be filtered through 

 blotting paper. 



Several different red stains are recommended. In one. 

 Brazil-wood chips are boiled in alum water and the filtered 

 solution is then applied to the ivory, which must previously 

 have been treated with a diluted solution of muriate of 

 tin. A red stain may also be prepared by making a solu- 

 tion of 4 parts of cochineal, 4 parts of cream of tartar, and 

 12 parts of tin solution, the cochineal being first dissolved 

 in warm tin solution and the cream of tartar added to the 

 resultant mixture; as a final step, a small quantity of sal 

 ammonia is to be gradually dropped in. 



A violet shade can be obtained by first placing ivory for a 

 few minutes in a much-diluted muriate of tin solution, and 

 then letting it lay for an hour in a decoction composed of 

 50 parts of Campeachy wood and 30 parts of water. Other 

 violet stains are given, one of them made by boiling for 

 an hour 2 parts of Brazil-wood chips in 5 parts of water; 

 the decoction is then to be filtered, and mixed with a solu- 

 tion of 12 parts of green vitriol to 25 parts of water. Lastly 

 1 part of aniline violet dissolved in 10 parts of alcohol, 

 the resulting solution having been carefully filtered, also 

 provides a good violet stain. 



To stain ivory black, it may be dipped in a solution made 

 by boiling 1 part of finely cracked gallnuts, and 4 parts 



*See Scientific American, Supplement No, 1677, p. 128, February 22, 1908. 



