Show DIAMOND MINES OF SOUTH AFRICA Since the first discovery of diamonds named in South Africa by a Dutch D farmer named Van In 1867 that sober continent rapidly became the principal producer of that precious gem gain For very many years practically the tho whole of the diamonds produced came from KImberly and with within in fa n fifty miles radius of that town says January Mines and Minerals In 1 1897 the tho first diamond mine in the Pretoria district known as the Schuller mine was IS discovered In 1892 an im immense Immense immense mense fillip was given to diamond pros prospecting prospecting pectin by the discovery in the same dis district district of ot the wonderful Premier mine The fillip thus given has resulted In the dis discovery covery vel of other rich mines including the Roberts Victor and the be besides besides besides sides dozens of others which are only par partially partially developed or proven and the de development development development and prospecting work Is being prosecuted in very many directions direct ona all aU allover anover over Oer South Africa t tAs As the working of diamond mines as distinguished d from alluvial workings Is practically restricted to South Africa that country has been obliged to evolve meth methods methods of mining adapted peculiar con conditions under which the deposit Is ts found These methods are strikingly different from those adopted In any other kind of mIning work A diamond minor pipe pine is the crater of an extinct t volcano and the erous ground forms the filling of that It Is generally conceded by geol geologists o that the diamond ground has been b forced up from unknown depths depth in the tana fArni f rm of liquid mud instead of molten ig igneous Igneous igneous rock In some respects therefore it would more closely resemble a geyser g ser than a volcano Where here the diamond ground is found within fifty lifty or feet reel of at the surface It tt is greenish yellow in color col color color or crumbles to the touch and la 11 f known as yellow ground At 1 depths below b blow low at atmospheric atmospheric influences it changes to a d greenish blue color becomes much harder and is known as blue ground or blue These craters or pipes are generally roughly circular In horizon horizontal tal or transverse section and penetrate to depths hitherto proved with little change of form but with very slightly decreasing decreasIng decreasing ing size In some cases as at De Beers the pipe is kidney shaped in others as at Roberts Victor the shape resembles a dumbbell and probably consists of or two I pipes connected by a fissure At De Beers BeerE the ground from or ora end of the kidney i is poor and not worked at Victor VIctqr Vict r i mine one end of the dumbbell is verj Ye 1 rich the other not considered profitable to i work From rom this and other evidences it would appear that the volcanic mud was I i not thrown up In one single outburst but that there were a series of ejections at varying periods and under varying condi conditions conditions conditions pipes are by no means uncommon in South Africa Altogether some hundreds have been located In different dif dlf different ferent parts of the tile country But the great majority of these do not contain diamonds In payable quantities The proved pay payable payable payable able mines cull can almost be Counted on tho the thoten thoten theten ten fingers After a pipe or mine has been l ted it is necessary to spend sev several several several eral hundred pounds on trial workings before a mine can be demonstrated as payable As the actual diamonds are so rare in occurrence the presence of certain asso associated associated minerals are generally taken as In Indicative IndIcative indicative of the existence of a true dia dla diamond diamond mond mine These minerals are garnets carbons a iron ore olivine and side and Their presence and condition Is generally relied on as indicative of a l diamond pipe If the deposit is alluvial the pebbles will willbe willbe be water worn |