218 Lieut. Newbold on the Geology of Egypt. 
of basalt, greenstone, porphyry, and serpentine are associated with 
the whole series. All the hypogene rocks assume a crystalline cha- 
racter near the granite or trap, the gneiss and hornblende schist be- 
coming garnetiferous and abounding in actynolite, both crystallized 
and compact ; the talcose schist also passes into potstone and ne- 
phrite with iron pyrites, as at Mount Baram ; the micaceous schists at 
Gebel Zerbara yield emeralds, avanturine, hematitic, and specular 
iron ore; and the clay-slate changes into basanite or flinty slate. 
2. Breccia di Verde—tThe argillaceous slate is overlaid confor- 
mably, in lat. 26° 8’, by the celebrated breccia di verde. This rock 
presents thick-bedded strata, which become more horizontal on re- 
ceding from the granite, and is composed principally of angular and 
rounded fragments of greenstone, gneiss, porphyry, argillaceous and 
flinty slates, serpentine and marble, also sometimes of light green com- 
pact felspar and hypogene rocks, cemented by aslightly calcareous 
paste of various shades of green and purplish red. No fossils have 
yet been noticed in the rock. ‘The cliffs composed of this breccia 
rarely exceed 200 feet in height above the level of the desert. 
3. Lower Sandstone——Above the breccia di verde occurs a sand- 
stone of apparently limited extent, and confined to the southern part 
of Egypt, passing thence into Nubia. It is displayed on both flanks 
of the anticlinal axis between Kossier and Ghennah, reposing near 
Bir Anglaise conformably on greenstone ; it is exposed also on the 
banks of the Nile, and, according to Lefevre, it ranges from a little 
south-west of Esneh (lat. about 26° 10') nearly to Syene or As- 
suan, 70 miles, where it is dislocated by the syenite, and near its 
junction with that rock passes into a conglomerate and becomes aga- 
tiferous ; it also, from the smallness of the fragments composing the 
breccia strata, and the altered crystalline structure of the mass near 
the plutonic rocks, often resembles certain porphyries, but the true 
nature of the rock is easily recognizable in the beds at a greater di- 
stance. 
This sandstone varies from a loose siliceous aggregate with a fels- 
pathic, calcareous or ferruginous cement, to a compact quartz rock ; 
and the pebbles in the interstratified breccia consist usually of chert, 
flinty slate, agate or jasper. Associated with the sandstone are occa- 
sionally thin beds of green and purple clay, containing gypsum and 
chloride of soda. Veins of white, brown, and amethystine quartz 
also traverse it, and copper as well as specular iron ore are stated to 
have been found in it near Hummamet. This sandstone was exten- 
sively used by the ancients. The vocal Memnon and many of the 
sphynges which line the dromos of the temple of Carnac consist of it. 
Mr. Newbold hesitates to decide the geological position of the 
formation, though Ehrenberg considers it to be the representative of 
the Quader sandstein, and Lefevre of the Keuper or Marnes Irisées*. 
4. Marine Limestone—The sandstone is overlaid conformably by 
a marine limestone, which covers the greater part of Egypt, from near 
Esneh to below Cairo, or from lat. 25° 10! to lat. 30° 2', and from 
* Bull, Soc. Géol. de France, tome x. 
