162 ARTHUR DIESELDORFF. 



the construction of silver iodide ; on the other hand the iodine in 

 the malachite (Nos. 8 and 9) must be present as hydrated oxy- 

 iodide of copper being the natural product of marshite, just as 

 atacamite is of nantokite. There is no doubt whatever, but that 

 small quantities of marshite 1 are present in the copper ores. 



The proof that it is distributed over much larger areas in New- 

 South Wales will be of interest, and leads the writer to hope that 

 further material will be sent him from the colonies, especially for 

 examination for the presence of bromine. The sample No. 8 from 

 Blayney, contains in all probability bromine, but there was not 

 enough of it to verify the tests. Should the percentage of iodine 

 go higher, say up to 01% for large quantities of copper ores, it 

 will doubtless be payable to extract it by sublimation in the flux. 

 Iodine amounting to 0*1% means 1 kilo per ton, the present price 

 is 30/- per kilo, while the cost of production would be 2/- to 3/-. 

 Iodine is recovered as a by-product in the nitrate factories of 

 Chili. The world's consumption in 1896 was 300 tons, value 

 ,£350,000, while Chili had in stock at the end of 1896, 900 tons. 

 To keep the price up enormous quantities of iodine are allowed 

 to go to waste annually. There is very little iodine now made 

 from seaweed. 



i See Journal of the Koyal Society of N. S. Wales, xxvi., 1892, p. 328. 



