Page:Proceedings of the Royal Society of London Vol 60.djvu/30

22 There was also 0.061 part of silver present in 1000 parts of the mass, the remainder being base alloy.

22 Mr. E. M atthey.

Another set of assays from the same ingot, but from the opposite end, at the point marked B, gave the following results :—

1 ........... 429*9 2 ____ 459*5 3 ........... 439*0 4 ........... 429*0 S ilv e r ........... 0*071 Ayerage .... 439*35

The difference in the amount of gold between the two opposite ends of the ingot was, therefore, no less than 223*10 parts in 1000. The base metal present was proved by analysis to be chiefly zinc, lead, and copper, as the following results will show on metal taken by a “ dip,” i.e., from the molten m etal:—

Z in c ........................... 15*0 Lead........................... 7*0 Copper....................... 6*5 I r o n ............................ 2*2 N ic k e l....................... 2*0 Silver......................... 7*0 Gold (by difference) 60*3 100*0

B. Another ingot of alloyed gold weighing 12*223 kilograms gave at different parts of the ingot the following results by assay:— Four assays on a piece of metal cut at a—top of ingot

Gold, Silver. 1 ............... 664*0 0*090 2 ............. 662*5 0 091 3 ............ 465*0 0*076 4 .......... 661*5 0*091