AbstractsBiology & Animal Science

"Ores containing copper, and especially copper matte, have always been very annoying in assaying for the precious metals. In assaying copper matte, and ores containing much copper, by the usual method of scorification, the losses of silver an gold are considerable, owing to the fact that in order to obtain lead buttons, which are soft and free from copper, repeated scorifications are necessary, and moreover it is impossible to obtain lead buttons which are entirely free from copper" – p. [1].