The investigation of stratiform/stratabound ore deposits associated with sediments and volcanics and ranging in age from Precambrian to Recent, has become a specialized branch within the wider scope of ore petrology. It is, by all means, not an entirely new field of endeavour and it has always had a place in economic geology, but an accelerated shift in both individualized and collective efforts in the study of the stratiform mineral accumulations has resulted in a large amount of dispersed data.

Coal is one of the relatively uncommon sedimentary rocks, but it is not rare because its estimated tonnage in the crust (of the order of 1013 tonnes; Fettweis, 1979) compares favourably with such rocks as carbonatites, nepheline syenites, phosphatic rocks or even chalk.

As an economic mineral commodity, coal lithosomes are perfectly and unequivocally stratiform and in the broad context consistent and genetically uniform, being always an organic sediment. In detail there are, of course, genetic variations, such as among the autochthonous and allochthonous coals, and among the coals of coalified plant (humites, humilitйs); microorganism and bituminous plant components (sapropelites); and pollen, resin, etc. (e.g. liptobiolites, resinites), derivations. The latter two derivations, however, are rare (Murchison and Westall, 1968). <...>

The Republic of South Africa is a metal producer of the first rank. Gold is the most important of the metals and up to the end of 1971, U.S.$ 32 billion had been realized from its sale. This figure was equivalent to 80% of the total value of all metals sold. The gold province is located on the Kaapvaal craton which is composed of Precambrian sedimentary-volcanic and granite-greenstone assemblages ranging in age from 1,750 to 3,500 million years. This craton forms the southern part of the Southern African Shield. No significant gold mineralization has yet been found beyond the boundaries of this shield. On the Kaapvaal craton, five Proterozoic sedimentary-volcanic basins lie on an Archean basement.  <...>

At a time when the DNA of Neanderthal Man has been sequenced and Jurassic World hints at possible future breakthroughs, however improbable, fossils have an undoubtedly high profile. Collecting fossils is a popular hobby. There is a wealth of helpful literature and websites which will help you to put an accurate name on your latest find, and to identify the various component parts of the skeleton.