GEOLOGICAL SURVEY OF THE TEERITORIES. 107 



the particles of quartz in this granite which points to a mechanical 

 origin. The rock is quite uniform in its structure. A mile or two in 

 the canon we came to a small village called Grauiteville. It is nea>r 

 here that the granite, of which the Mormon temple is being built, is 

 quarried. Instead of working into the rock on the sides of the canon, 

 the quarrying is confined to the huge blocks of granite which are scat- 

 tered over the bottom on both sides of the creek. Some of these blocks 

 are immense, measuring 30 feet square. They aresplitinto the required 

 size. Our road for about five miles leads us between the granite walls 

 that tower far above us, surmounted by dome-like masses, whose summits 

 are covered with snow, giving origiii to the numerous falls and cascades 

 which abound on the sides of the caiion. The Little Cottonwood Creek 

 flowing past us flills about 500 feet to the mile. It rushes along furiously 

 over its rocky bed, seeming to be at war with the immense bowlders that 

 dispute its right of way. As we j)roceed we leave the granites behind 

 us, and above us project the sharp, jagged edges of quartzite beds. 

 These quartzites have a reddish color, and are followed by slates upon 

 which rest thick beds of white limestone. The lower beds are crystalline 

 and probably Silurian, although I was unable to find any fossils in them. 

 The upper layers are dolomitic, and are Carboniferous in age. It is in 

 these limestones that the ores occur. The piincipal mine is the Emma. 

 Unfortunately, owing to a disturbance at the time of our visit, 1 vias 

 unable to see the Emma mine, but visited the Flagstaff and the Sliver 

 Star. I quote the following analysis and remarks upon the ore of the 

 Emma mine from an article by Professor Sillimau:* 



I am able to present an analysis of an average sample of 82 tons (=183,080 pounds) 

 of first-class ore from the Emma mine, made by James P. Merry, of Swansea, April, 

 1871, which is as follows : 



Per ceBt. 



Silica 40,90 



Lead 34.14 



Sulphur 2.87 



Antimony 2.27 



Copper 0. 83 



Zinc. 2.92 



Manganese 0. 15 



Iron 3. 54 



Silver , 0.48 



Alumina 0. 35 



Magnesia 0. 25 



Lime 0. 72 



Carbonic acid „ 1.50 



90. 42 

 Oxygen and water by difference , 9.58 



100. 00 



The qnantity of silver obtained from this lot was 156 troy ounces to the gross ton of 

 2,240 pounds. 



This analysis sheds important light on the chemical history of this remarkable 

 metallic deposit, and will aid us in the study of. the paragenesis of the derived species. 

 It is pretty certain that all the heavy metals have existed originally as sulphides, and 

 we may, therefore, state the analysis thus, allowing 8.52 i)er cent, suli^hur to convert 

 the heavy metals to this state : 



Silica 40.90 



Metallic sulxihides 52. 60 



Al, .35, Mg, .25j Ca, .72; Mn^ Mn, .20 1.52 



95.02 

 Water, carbonic acid, and loss = 4. 95 



'American Journal of Science and Arts, vol. iii, page 198. 



