392 



GEOLOGY OF THE DENVER BASIN. 



composition quite unattainable in regions of slight dip, where but a com- 

 paratively small thickness is mined at a time. 



The manufactured product from the Fox Hills clays is a pressed brick 

 of* the finest quality and color. The machines in use and the process 

 employed are practically those of Other portions of the United States. 

 The product is consumed in Colorado, chiefly in Denver. 



The Pleistocene and Denver formations, in the vicinity of Denver, 



rank next to the Fox 1 1 ills in the importance of their yield and manufac- 

 tured product. The latter is large, both in pressed and common brick. 



Clay product of the Denver Basin for the year 1894? 



1 From Mineral Resources of the United st;itos. 1894, V . s. Geological Survey. 



SECTION III.— IUTLDIXG STONES. 



INTRODUCTION. 



Within the area of the Denver Basin but a single important quarry of 

 building stone, that at ( S-lencoe, has been opened. Beyond, however, both in 

 the foothills and on the adjoining prairies, there are several, affording great 

 variety in texture, hardness, color, and adaptability to architectural require- 

 ments. That considerable rock, of an excellent quality and well suited to 

 many of the uses arising in the construction of buildings, does exist within 

 the confines of the Denver Basin, and that the beds are of sufficient extent 

 to afford a satisfactory and continued yield, together with a necessary 

 economy in production, the observations of the present survey reasonably 

 affirm. The nondevelopment within the basin is due in part to a difference 

 in the character of the stone from that beyond, and in part to the early 



