Bisbee daily review., 1906-06-10

ltaDSnsly unlli lue sun anu ehS hot-. cause 1t to diintegraae. The effect of the exposure to heat and mois,ure Is remarkable. Tho large pieces oi I'oiue begin to crumble immediately and the diamonds lying buried in them are thus released. But they are in- visible. During all the time l was in charge of the Debeeis mines l never found a diamond on the drying floots. To hasten disintegration the blue sround is stirred up daily by harrows ust as a farmer prepares the soil ol ais field for seed. Formerly the har-
 ows were drawn by mules, but now se use traction engines. The length
 )f time required for the blue ground
 to lulverize depends upon the season
 ,f tbe year and the amount of rainfall sometimes six months. sometimes year
 After it has reached certain con dition the large pieces, which have not iisintergrated, are removed from the floors and crushed in breakers. The well disintergrated blue ground is carted in automatic trucks to washing machines, where it is reduced to the consistency of thin mud and passed through d series of screens in order to catch the large pieces of rock. The magnitude of these operations may be appreciated when I tell you that near ly 5000, 900 truck loads, or 100000 tons, of blue ground have been wash ed in a single year for the sake Of few bucketfuls of diamonds. It would from a block larger than any cathedral in the world, overtopping the spire of St. Paul's, while very small box would hold the gems.
 After the end of each days work the pans through which the mud has passed are cleaned up and the con tents, consisting of diamonds and other heavy but valueless materials, are sent to the 'pulsator,' where they are sized by passing through steel sieve with holes from one-sixteenth to tiye-eights of an inch in diameter. The finest sizes are conveyed to a wash ing pan and the coarser ones pass to revolving picking tables, where dia- ElonGs of the largest size may be seen and removed without being exposed to the risk of being crushed by a further pulyer;gation. The remainder pass through the screens into pointed boxes from which they are carried over a series of trays covered with thick Sreese. This is q curious process. Formerly all of the particles that did not go through the screens were drop ped upon sorting tables, where the diamonds were picked ou tby hand. This was q slow, tedious and imperfect process. A great many gems were lost and carried away with the tail inEs, until Fred Kristen, one of the employees, asked to be allowed to catch the diamonds by placing a coat Of greese upon the surface of the table upon which they were dumped. Kir- sten had noticed that oily substances, such as axle grease and white and red lead, adhered very tenacious!y to diamonds, and argued to himself why should not diamonds adhere to grease?
 Tn this way he made the remark able discovery that jewels alone will adhere to grease, while all other min erals will pass over it. Since the discovery of this curious affinity it haS been demonstrated that rubIes. emeralds and sapphires can be caught ID the same way. Therefore all of our streams from the washers now pass oyer. sloping tables made of cor rugated iron and thickly covered with grease. Only about one-third of one per cent or diamonds escape the first taDie, while the remainder are re covered almost to 9 stone on the sec ond tale. This graease will not cling to anything but a precious stone, Small bits of iron pyrites. brass nails from miners boots, pieces of con Der from the detonators used in blast ing and an infinite variety of other metallic articles pass oyer 1t without being detained an instant, but 1t will catch diamond every time.
 The diamonds are placed on sort ing tables. where they are cartfulIv separated with reference to size. color and purity They are then washed In mixture of acids to clean them or extraneous matter, and are made up i'll parcels to be delivered to inc representative of the syndicate of London diamond merchants who have purchased the entire annual output of the De Deers mines for several years
 All the sorting is done by the trained naked eyes oI experts. No Imagnifying glass Is ever used. We employed ten sorIers. two women and eight men, all Europeans, and trained alIrenuees to succeed them in case any should leave. More than s2O. GOO. :. Vec worth of diamonds pass annually through their hands. For the safe Keeping of the gems there Is a strong vtuit of very thick concrete, fire and burglar proof, secured by several locks of the latest designs, with different Keys, which are kept by the several officers of the company. IL was nee esssry for all of them to be present at the opening and closing of the room. In addition to these precautions there are electric alarms and armed guards.
 After the diamonds are sorted they are put into little square tin boxes which fit Into tin cases like dispatch boxes. each of which will hold about forty Of the smaller ones. They are delivered 10 the buyers at the office CT the latter. and paid for on delivery in cash or in bills on ondon. Diamonds have fixed value. which Is reached by q recognized formula, according to the number of karats. The word karat is derived from the Greek Ike ration,' the fruit of a variety of acacia, whose seeds weigh four grains ayoir- n.