Page:Quarterly Journal of the Geological Society of London, vol. 33.djvu/1029

Rh Cadgwith village to the level of the main plateau above the sea, we again find the serpentine. A quarry here (in 1876) showed the junction with the schist very well. The former rock overlay the latter (which had a dip of some 30°) with a rather irregular junction; but here, as in other cases, it seems to have generally forced its way fairly evenly along the plane of bedding. The serpentine (no. 6) is very compact in texture, and varies from a claret-colour to an olive green, both varieties being veined and mottled, the former with dull green and bright red, the latter with a purplish tint; occasional layers of greyish-green steatite occur.

The serpentine in the cove beyond is mottled light and dark green. This rock now continues to form the cliffs above the sea for some distance. About half mile from Cadgwith (measured in a straight line) the shore is strewn with huge boulders and overhung by cliffs of a dark serpentine. This rock is almost as black and compact as that of George Cove; but the surface is varied by a vein- like mottling of very dark olive-green, and by bronzite crystals about 0⋅2 inch wide with a bright submetallic lustre (no. 10); it weathers a dull earthy green.

Some 100 yards from this spot, along the shore, we reached an apparently faulted junction of the serpentine and hornblende schists. Directly after, the serpentine sets in again, overlying the other rock, following nearly the plane of bedding. The hornblende schist is extremely altered; some bands in it are in colour and texture very like ordinary vein granite; but, after most careful examination, I feel convinced there is no true granite here. The ends of the strata are bent over on the southern side; and in the lower part a coarse breccia of schist and serpentine separates the two masses of these rocks. There is a similar breccia, though less irregular, on the other side, where the base of the serpentine is greatly decomposed, the rock assuming an earthy aspect, of a mottled dull greenish or reddish grey colour, veined with indian-red, having scarce any resemblance to normal serpentine. A little further on are four masses of hornblende schist, one after another along the shore, caught up in the serpentine (fig. 5). Parts, again, of these are