COLOEADO. 485 



tunnel. The demand, however, had not, thus far, called for that degree of 

 activity. During the winter about 20 or 30 tons per day were mined. 

 The price of mining, paid to the contractors, was $2 j)er ton, delivered in 

 wagons at the mouth of the tunnel ; and the price obtained from buyers was 

 S4 per ton. The selling price in Denver, 24 miles distant, at that time, was 

 from $10 to Sl2 per ton. 



At Murphy's mine, 5 miles from Golden City and 12 miles from Denver, 

 the seam worked is 16 feet thick, and, where opened, is upturned so as to 

 stand vertically. It is opened, where cut through by Ralston Creek, by tun- 

 nels, the coal being broken down from above the level of the tunnel. The 

 coal is of excellent quality. A force of about 18 men was employed, pro- 

 ducing about 35 or 40 tons per day. The cost of mining, that is, the contract 

 price paid to miners, was $1 50 per ton. Denver furnishes, thus far, the 

 principal market for the coal of this mine. 



Precious Metals. — The metal-bearing veins occur in the more elevated 

 portion of the mountains, and form, at those points where developed in Colo- 

 rado, parts of a great system, which is generally known as the Mineral Belt, 

 This belt, stretching along the range from south to north, has only been 

 explored at intervals ; but, although broken here and there by unproductive 

 regions, is probably, in a general sense, continuous for many hundreds of 

 miles. Its limits are unknown, but it probably traverses the domain of 

 the United States and, extending far beyond our boundaries, contains many 

 new fields of mineral wealth that are still to be discovered and developed. 



Superficial examinations and prospecting have been carried on over a 

 considerable portion of its extent in Colorado, but persistent exploration, with 

 a view to the development of mines, has thus far been confined to a few 

 points. The mining regions thus opened extend from the central part of 

 Boulder County in a southerly, or south-southwesterly, direction through Gil- 

 pin, Clear Creek, Summit, and Park Counties, forming a belt of ill-defined 

 limits, but, so far as at present developed, from five to ten miles "wide and 

 from seventy-five to one hundred miles long. At many points along this belt 

 metaUiferous veins have been found, occurring in groups that are separated 

 from each other by intervening barren regions. These veins are generally 

 inclosed in granitic and gneissic or schistose rocks of metamorphic character. 



