436 GEOLOGICAL EXCURSIOM TO THE ROCKY MOUNTAINS. 



(14,147 feel — 1,312 m.). A notable feature of the landscape is Table 

 mountain, a gently-sloping mesa at t lie base of the mountains, directly 

 west of Denver, "where a basalt sheet has protected the soft underlying 

 strata from erosion. Behind the mesa is the city of Golden. 



Denver is the commercial center of a very Large territory. It is of 

 special importance through its relations to the mining industry of the 

 mountainous region to the westward, for it is the greatest ore market 

 of the Rocky Mountains. Prom mining camps, not only in Colorado. 

 but also in the surrounding States and Territories, ore is brought to 

 Denver, sampled, and sold in the public market. 



There are in the city three very large smelting establishments. Of 

 these the Boston and Colorado Smelting Company, whose works are in 

 the suburbs at Argo, deals principally with the more refractory ores, 

 and pays especial attention to ores containing copper, silver, and gold. 

 The process is a modification of the Ziervogel process. The gold is 

 separated from the copper by an operation which is kepi secret. The 

 Omaha and Grant Smelting and Refining Company, whose refining 

 works are at Omaha, is said to be the largest establishment of its kind 

 in the world. Argentiferous lead ores, such as those of Leadville and 

 Aspen, are the ones most sought for here, as also at the Globe Smelt- 

 ing Works, near Argo, where some of the largest lead furnaces in the 

 world are in operation. 



Among the public buildings worthy of note is the State capitol, 

 now being erected on a beautiful site on Capitol hill; the Arapahoe 

 County court house on Sixteenth street, built of a grayish sandstone 

 from the Laramie Cretaceous, and the High School building, one of the 

 largest school edifices in the United States. In the upper corridors of 

 the last-named building are temporarily displayed the collections 

 of the Colorado Scientific Society, which are well worthy of a visit, 

 especially for the mineralogists. 



A mining-stock exchange, started a few years ago, is now erecting a 

 handsome building for its use. 



The visitor will, undoubtedly, note the great variety of beautiful 

 building stones used in Denver. These are nearly all the product of 

 the State, and many of them come from quarries near the city. From 

 the Archean conies a coarse-grained red granite and a tine-grained gray 

 granite. The red sandstones of the Trias and Jura are much used. 

 White sandstones come from the Dakota Cretaceous, or much more 

 commonly from the Fox Hills or Laramie Cretaceous. The latter 

 rocks are very easily worked and have various soft tints of gray, 

 brown, or yellow. Beautiful marbles of white and variegated colors 

 occur in Colorado, but have not yet been used to any great extent. 

 One of the most popular building stones, especially adapted for resi- 

 dences, but also used in the Union Depot and in other large buildings 



