372 Geological Survey of the Island of Jersey. 



CHAUZEY. 



A group of small islets and rocks, eight miles N. W. of Gran- 

 ville, about eight miles long and two and a half wide at an 

 average. Whatever irregularity may be presented by the 

 Jersey rocks as to the number and proportions of the granitic 

 ingredients, those of Chauzey, though similar on the whole, 

 differ distinctly from the above in the uniformity and more 

 equal proportions of their constituents, in their unmanageable 

 irregularity of stratification, in the rounded forms, and fre- 

 quently gigantic size of the more or less detached blocks on 

 the surface, and in the singular tendency of these last to scale 

 off, when attacked by the elements, in coats concentric to their 

 external and rounded surface. 



This rock is almost invariably such a mixture of quartz, fel- 

 spar, and mica, as is exemplified by Nos. 59 or 53. Some- 

 times, but comparatively seldom, the felspar and quartz assume 

 a dark red colour, as No. 60. Another, although a minor point 

 of difference, is, that this rock at Chauzey contains very nume- 

 rous isolated portions of semi-transparent quartz, not exceeding 

 perhaps 20 cubic inches, and also of closely aggregated mica, 

 occasionally containing schorl (61) : 59, a, is a specimen re- 

 sembling grauwacke, from a block imbedded in 59. As to the 

 stratification, it is very marked, often as much so as the newest 

 rocks, but varying in every direction. 



With reference to external form and size, the blocks have 

 exactly the round boulderstone appearance, and often the 

 arrangement of the Cheesewrings ; sometimes the detached 

 are nearly cubical, having a length of side of 12 feet. 



In fact, the whole group is one quarry of the finest building 

 material of any dimension : Granville and St. Maloe's are built 



