270 DESCRIPTIVE GEOI.OGT. 



the first anticlinal, are found interstratified beds of dark-green liornblende- 

 schists, which, owing to their sharp contrast of color with the including rocks, 

 and the steep angles and the contortions of the beds, have a slight resemblance 

 to a dike of intrusive rock, for which, indeed, they might be mistaken by a 

 careless pr unpractised observer. These hornblende-schists were also found 

 on the flat-topped hill to the westward near the Red Creek divide. To the 

 unaidedeye,the hornblende-schists seem composed exclusively of hornblende; 

 but, under the microscope, the intervals between the hornblende prisms are 

 found to be filled with colorless quartz and a few feldspar particles. They 

 closely resemble those already described from Bruin Peak in the Park Range. 



About midway in the canon are found a series of fine-grained, white 

 talcose mica-schists, containing large dodecahedral crystals of dark garnet, 

 which resemble in a remarkable degree the well-known paragonite-schists 

 of the St. Gotthard in Switzerland (found at Monte Campione near Faido). 

 They contain disthene, or cyanite, in pale-blue crystals, like the European 

 occurrence, and, moreover, large, well-defined crystals of staurolite, frequently 

 crossed in twins. Under the microscope, the paragonite apjDears in col- 

 orless hexagonal laminae, irregularly disseminated throughout the rock, as in 

 the Swiss occurrence, but, unlike the latter, seems to contain no microscopical 

 disthene or staurolite ; it does contain, however, some microscopic tourma- 

 line. The staurolite crystals are seen, under the microscope, to contain a 

 large proportion of free quartz in rounded grains. On the cliff's to the west 

 of the mouth of the canon, as already observed, are some fragmentary beds 

 of the Weber Quartzite, dipping 15° north, resting unconformably on the 

 upturned edges of the Archaean strata. 



In the character of the quartzitic and hornblendic strata, these rocks 

 resemble the Archseans of the Rocky Mountains; but the paragonite beds 

 have not before been observed, and the presence of white mica is also unusual. 

 It has, however, been considered that they may be referred to the upper or 

 Huronian portion of that formation. At the head of Willow Creek, some min- 

 eral-bearing veins have been discovered in these rocks, carrying red oxide 

 of copper and some silver, but, at the time of our examination, had not been 

 sufficiently opened to enable us to form an opinion of their probable value. 



