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The chloritic sand is regarded by many geologists as a littoral deposit of the Chalk Ocean, and therefore contemporaneous with part of the chalk marl, and even, perhaps, with some part of the white chalk.
Distinctness of Mineral Character in contemporaneous Rocks of the Cretaceous Epoch. Fossils of the White Chalk. Lower White Chalk without Flints. Chalk Marl and its Fossils. Chloritic Series or Upper Greensand. Coprolite Bed near Cambridge. Fossils of the Chloritic Series. Gault. Connection between Upper and Lower Cretaceous Strata. Blackdown Beds. Flora of the Upper Cretaceous Period.
The predominant rock is mica-slate, with thick folia of quartz, very frequently alternating with and passing into a chloritic, or into a black, glossy, often striated, slightly anthracitic schist, which soils paper, and becomes white under a great heat, and then fuses.
The rocks here consist of several varieties of gneiss, with the feldspar often yellowish, granular and imperfectly crystallised, alternating with, and passing insensibly into, beds, from a few yards to nearly a mile in thickness, of fine or coarse grained, dark-green hornblendic slate; this again often passing into chloritic schist.
For, as the land went on sinking, and the cretaceous sea widened its area, white mud and chloritic sand were always forming somewhere, but the line of sea-shore was perpetually shifting its position.
The blocks of the northernmost train, Number 7, are of limestone derived from the calcareous chain B; those of the two trains next to the south, Numbers 6 and 5, are composed exclusively in the first part of their course of a green chloritic rock of great toughness, but after they have passed the ridge B, a mixture of calcareous blocks is observed.
On the road to Catia we see the chloritic schist passing into hornblende schist. The sea at the foot of Cabo Blanco throws up on the beach rolled fragments of a rock, which is a granular mixture of hornblende and lamellar feldspar. It is what is rather vaguely called PRIMITIVE GRUNSTEIN. In it we can recognize traces of quartz and pyrites.
The river could still be followed a short distance further upwards; and in its bed there were disjointed fragments of talcose and chloritic rocks. The net employed in fishing appears to be suited to the locality, which is a shallow river, full of transparent blocks.
At the distance of several yards occurs a smaller block, 3 or 4 feet in height, 20 feet long, and 14 broad, composed of the same compact chloritic rock, and evidently a detached fragment from the bigger mass, to the lower and angular part of which it would fit on exactly.
This is especially so at Bergen Hill and Staten Island. They occur in amorphous masses generally, and may be distinguished by being so soft as to be readily cut by the finger nail. I will detail further upon the soapstone forms in discussing the localities on Staten Island, and the chloritic form under the head of "Weehawken Tunnel."
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