Microchemistry of the precious metal elements

The precious metal elements to be discussed in this paper are platinum, palladium, rhodium, ruthenium, iridium, osmium and gold. Considerable attention has been devoted successfully in the past to means of identifying gold and silver in minerals, but the microchemistry of the remaining six elements has been generally neglected. In part, this neglect results from the complex chemical behavior of these elements and, in part, from the assumption that the platinum-palladium group of minerals are rare. Recent discoveries of noteworthy amounts of several of these elements in many ores emphasize the need of some method whereby the composition of unknown minerals encountered during mineragraphic investigations can be tested for the presence of the precious metal elements.