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Instruments and techniques for the study of gold and other precious metals in their ores are available. Nobody ever denies the importance of the knowledge of the microcomposition of the ore for proper recovery planning. Yet it seems as if generally very little is done towards the use of systematic studies before separation is attempted. Let us discuss in some more detail how some metallurgists and mineralogists function and try to understand why their way of operating is largely responsible for such an apparent contradiction.

The variables discussed in the previous chapter are found in the literature or are determined experimentally.

During the past 30 years and largely following the advent and development of computers, an incredible advance has taken place in many sectors of modern technology, for example medicine, dentistry, the automobile industry, the TV and stereo, the appliances industries. This advance has happened so quickly that a wide intellectual gap has developed between the older and younger generations. Many people over 40 cannot believe that a child under 10 understands and operates computers better than they can, if they can at all.

There are many differences between gold and silver and several affect the decisions regarding ore exploitability first, then the choice of recovery agents and techniques. In order to understand these differences (listed in table 12), we need to go back to the variables discussed in chapter 3.

So precious metal deposits are more complex than metallurgists believe. Let us examine what makes the applied study and understanding of these deposits complex.

Metallurgy, the study of the physical and chemical properties of metals, is a relatively new science. Many of the elements in the periodic table were discovered during the past 250 years (see chapter on base metals and table 17). Their systematic study has been carried out for less than a century.

Platinum group elements are ruthenium, rhodium and palladium (of similar weight as, but lighter than silver, the next element in the periodic table by atomic number) and osmium, iridium and platinum (of similar weight as, but lighter than gold, the next element in the periodic table by atomic number). As opposed to gold and silver, known probably since the stone age, the first certain discovery of platinum, in the alluvial deposits of the Rio Pinto – Columbia, is as recent as 1741. Platinum was introduced to Europe by Sir Charles Wood who brought it to England during that same year. Osmium and iridium were isolated together from the residues of platinum ores in aqua regia in 1803 or 1804 by English chemist Smithson Tennant. The existence of rhodium and palladium was established in 1803 by English doctor W. Hyde Wollaston. Ruthenium was recognized as an element in 1844 or 1845 by Russian chemist C.E. Claus.