Excerpt from A Manual of Practical AssayingFire-assay determinations involve the separation of the metal sought from the other constituents of the ore by the aid of heat and suitable ¿uxes, and its estimation by weighing in a state of purity. For example, if the object is the determina tion of lead in an ore, the ore is mixed in a crucible with suit able ¿uxes and fused. The lead is reduced to the metallic state, in which condition it is readily detached from the slag for weighing.About the PublisherForgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.comThis book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully, any imperfections that remain are intentionally left to preserve the state of such historical works.