GREENSTONE. 



247 



x 



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195. — Compact greenstone, containing a little iron 

 pyrites. From a dyke traversing chlorite and mica schist. 

 The Skerries, Anglesea. 



196. — Compact greenstone, with a weathered surface. 



Rhosmynach, Anglesea. 



197. — Diallage rock, apparently cutting through ser- 

 pentine. (See "Report on Cornwall/' p. 98.) — Penvose, 

 Landewednack, Cornwall. 



198. — Compact greenstone, apparently intruded amon" 

 argillaceous slates. Employed for roads, for which it is an 

 excellent material. — Egloshayle, Cornwall. 



199. — Greenstone. — Bryn Fuches, Anglesea. 



200.— Greenstone {fine grained), formed of hornblende, 

 felspar, and carbonate of lime. This forms a boss of rock, 

 apparently forced up among the adjoining slates and brec- 

 cias. It may be remarked that the latter, which occur on 

 the southern part of the hill, do not contain any portion of 

 the trappean rock near them. — Dmas Hill, near Padstow, 

 Cornwall. 



201. — A kind of trappean rock, having a semi-mechani- 

 cal origin, and associated with a conglomerate (No. 119) of 

 the slate series. This rock is quarried, for building stone, 

 at the cliff close to the river. — Opposite Cant Hill, Padstow 

 Harbour, Cornwall. 



202 — Greenstone. — This rock occurs at the extreme 

 point of the head, and is continued outwards in a western 

 direction under the sea-level, as is seen by rocks which 

 appear at low water. Without the protection of its green- 

 stone point, Park Head would be cut back, by the incessant 

 action of the breakers, to the general line of coast on each 

 side of it— Park Head, St. Eval, Cornwall. 



203. — Greenstone with a small quantity of iron pyrites. 



This rock forms the northern pa^rt of the Head, and con- 



w 3 known as the Millup, or Mirrup Rocks, 

 which extend eastward into Polventon Bay. The green- 

 stone has evidently been intruded among the adjacent schis- 

 tose rocks— East side of Trevose Head, Cornwall. 



Upper 

 Gallery. 



Wall-cases 

 6 and 7. 



