34 RESURVEY OF CRIPPLE CREEK DISTRICT. [BULL. 254, 



facts upon future mining development. For such a forecast of the 

 future moderate probability is all that can be claimed. 



As has been pointed out in the preceding pages, the largest known 

 ore bodies of the district are apparantly confined within a zone which 

 extends from the surface to a depth of 1,000 feet. In general, explo- 

 rations below that depth have been much less satisfactory, as regards 

 quantity of ore, than explorations above. It is certainly true that 

 some large ore bodies as yet show no sign of depletion in depth, and 

 that some good pay shoots have been found at a depth of 1,400 to 

 1,500 feet. On the other hand, the number of ore shoots that have 

 been exhausted with increase in depth is considerable. 



It is probable that the ore bodies, known or unknown, occurring 

 below the 1,000-foot zone are neither so large nor so abundant as 

 those nearer the surface. The discovery and exploitation of these 

 (Jeeper ore bodies is, moreover, beset with increasing difficulties, chief 

 among which is the problem of dealing with the underground water. 

 For these reasons it is unlikely that the zone between the 1,000-foot 

 and 2,000-foot levels will yield as much as the zone between the sur- 

 face and the 1,000-foot level, but the possibility is not denied that 

 sorce strong fissures may carry payable ore to far greater depths than 

 those jet attained. 



As regards the zone above the 1,000-foot or 1,500-foot level, it is 

 well to bear in mind that it still contains much ore, both as parts of 

 known ore shoots and as yet undiscovered ore bodies. It is certain 

 that many of these undeveloped ore bodies will be mined in the near 

 future and that this zone will contribute the most important part of 

 the production. 



It is probable that the production of the district, while exhibiting 

 fluctuations, will on the whole slowly decline. New ore bodies will 

 undoubtedly be discovered from time to time, and individual mines 

 may be as profitable in the future as they have been in the past, or 

 even more profitable. An increased output may be expected to 

 follow each successful step in deep drainage. But existing conditions 

 indicate that if the maximum production of $18,000,000, in 1900, is to 

 be surpassed the increase will be due to the ore bodies encountered in 

 the upper zone. 



