Bisbee daily review., 1918-08-13
DIAMOND DRILL Is AT WORK IN MAYER
 DISTRICT
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MAYER, ArlZ., Aug. Fly cry inter- estlng wOrk IS being accomplished III the Elue Bell anu bngnamptOn mines in the Mayer district through the use or the diamond drlu lh exploration TOT new bodies or ore. The prevailing schist formation in which the ore oc- CUTS is vertical or Hear yerucal and the ore itself is found in lenses when conform 10 the angie Of the formation In the flat porphyry 0eposIs or cop per ore the prospecting with drIils Is dOne with perpendicular nCles Wuile III the schlst mIneralizeu zones in thk Mayer district, the holes are all run horizontally wnicn cut across the IOr- nation east and west, the work 'Delug done on a deep level or the mine.
 The Arizona Bmghampton company leads in the amount of diamond drill ing done thus tar in this district. The work is being done by the Cannon Brothers Exploration company, former ly ot Butte F. C. Cannon manages the work at the Binghampton mlne and a brother Fred has d number of contracts in the Oatman district.
 4 government permit is now neces- sary before diamonds can De purchas- ed. The buyer must satisfy the gov ernment that the stones are to be used fer the purpose Of drilling in the Unit ed States. Since a great deal depends upon the quality of the stones, the Cam non Brothers usually make their pur- chases Of diamonds from allotments sent rom the east to a bank where the selections are made. Formerly. black diamonds weighing one and quarter carats were used in the bit, six to the set. It has been found that diamond chips" about r. to the set dc better work. The diamonds in drill set are worth about $l,00O, the cost of the black diamond being'about the same as the brilliant A bit will drill from 40 to 60 feet without being reset. The cost per foot for diamond wear is about 90 cents. The cost per foot of drilling is from S25O to $500, 1t being necessary to employ two men the runner and the helper. The runner receives $500 per day and must be ex- perienced in the use of diamonds in drilling.
 The kind of drill machine used In the BinghampJon is known as the Sul- livan Type E which is a small single cylinder machine using one and a quarter inch bit The core is seven eights inch in size and the length uf the core is feet The holes in both the Blue Bell and the Bmghampton are run from loo to 200 feet in length and are not spaced any regular ais tance but are usually around 100 tO l5O feet apart. One S-hOur shit can drill about 15 feet Of hole. As mdcl air is used to run the diamond drill as Is required for two Leyners anu as much water as for one LeyneT.
 A total of 1000 feet has been drilled at the BinghamptOn cut up into 45 holes. It is the plan Of the company to do twice as much drilling in tLe next few months. The Blue Bell yOrk amounts to % holes from 100 to 2p0 feet long and about 120 feet apart. Most oi the drilling in the Blue Bell has been done on the 80O-ft level while iH the BinghamptOn several lev els have been exploited. The average core recovery is i00 per cent in che quartz and ere formation and about S5 per cent in the softer schisJ.
 The main object oi diamond drilling in this fashion in this Mayer district, i3 to discover unknown bodies of ere which are supposed to exist in a min eralized zone. The core shows the formation through which it passes and both the drillings and the core can be