ON TINKALZITE (BORATE OF LIME AND SODA), FROM PERU. 47 



cooling. It is of a yellowish colour, and is employed by the natives as a 

 healing medicine. Probably it might be a useful oil for other purposes, if 

 procurable in sufficient quantities. 



There are many other oils and oil-seeds quoted in India, some only 

 by their native names, others of very questionable utility, or only to 

 be obtained in small quantities and at extravagant prices, which we 

 have consequently omitted from this paper. If this effort at supplying 

 a condensed list of the vegetable oils and fats of India is not considered as 

 complete as it might have been, it presents, at least, for the first time in a 

 collected form, the names and sources of all the more important of the 

 oleaginous products of our Indian Empire. 



ON TINKALZITE (BORATE OF LIME AND SODA), FROM PERU. 



BY T. L. PHIPSON, 



Phil. Nat. Doct. Bruxelles University; 

 Member of the Chemical Society of Paris, &c. <ke. 



The useful mineral of which I am about to speak was discovered only 

 a few years ago in the deposits of nitrate of soda in Peru. It is now im- 

 ported into Europe in considerable quantities as a substitute for borax. 

 It was first examined in 1850 by M. Ulex, who found that it contained 

 boracic acid, lime, and soda ; but the analysis published by this author 

 shows too small a quantity of water, and too much boracic acid. In 1859, 

 M. Kletzinsky received some samples of this same mineral from the Western 

 Coast of Africa, and the analysis he has made of them coincides pretty well 

 with my analysis of some specimens from Peru. 



Tinkalzite is found in the layers of nitrate of soda of Southern Peru, 

 in the shape of globular masses, which the natives call tiza, and which 

 vary in size from that of a nut to that of a potatoe. The outer crust of 

 these tubercles is rather hard ; but they are easily broken, and are then 

 seen to be formed, in the interior, of a mass of crystalline needles, intersect- 

 ing each other in all directions, and of a brilliant white satiny appear- 

 ance. Often these globular masses contain reddish crystals of gypsum and 

 other minerals ; and they always contain a certain quantity of common 

 salt, which gives to the mineral a brackish taste. 



"Water extracts from tinkalzite all its chloride of sodium and borax ■ 

 acids easily dissolve the whole mineral, leaving only a small residue of 

 very fine sand. 



The density of tinkalzite I find to be 1-93 (according to M. Kletzinsky, 

 = 1-9212 ; and according to M. Ulex, the satin-like fibres =1*8). 



