Systematically prospection of potential gold deposits may be done by drilling, which secure to the metallurgist and geologist a true outline view of what they may expect from the deposit. it is well established fact that the only reliable and satisfactory method of drilling prospect holes is by means of diamond core drills. These have entirely superseded the old churn drill procedure used in the XIX century and the first years of the last century. The business of gold mining is being rapidly evolved from the traditional mining activity to an important commercial activity, in which it is clearly recognized that the increased profit potentialities compensate for certain added risks which are involved in its prosecution.
From its nature, it is frequently impossible with any degree of certainty to estimate what result may be expected from a given gold exploration activity. The uncertainties are primarily the average milling gold grade of the deposit, and its width and extent. The manner of settlement these in the past is not a complete method. In the case of a gold company possessing a reef outcrop, it has been thought sufficient to take a few specimens of the deposits at surface, ascertain their value, and establish from that a basis of calculation from which is deduced the worth of the entire holding. Shafts are sunk, a gold recovery plant erected, and everything proceeds satisfactory until the full scale operation starts. A result totally disappointing and absolutely non-payable is obtained. The company suspends operations and the deposit is blighted.
The reason for this, leaving premeditated fraud out is clear, the ultimate result is only that which would be attained by similar procedure in any ordinary commercial business. A manufacturing firm, for instance, only goes into production when its field of demand has been prospected by those means which industrialism provides. Its entire resources are not launched into a business until its full nature is understood and its potentialities have been gauged. If this in necessary in a normal business, something similar and more is necessary in the business of gold mining, and drilling programs a very important part.
The drilling machine makes a perfectly smooth hole to any depth or in any given direction from vertical to horizontal, bringing to the surface a solid section or core of all strata passed through in the order in which they lie, determining also the exact depth of any particular rock, its thickness and characteristics. The diameter of the core, which varies from 27 to 85 mm, according to the nature of the formation under operation, allows of thorough examination and testing, and the presence or otherwise of the ore or mineral sought is settled. The requirements of diamond drilling machine are many and exacting. It must be strong, simple and durable, economical, rapid in operation and above all, its work must be accurate and reliable so that the results derived from it shall be known to be corrected, and they have an impact the extensive processes of shaft sinking and equipment, as well as the investment of large amounts of money.