Vol. 65.] OVERTHKTJSTS AT TINTAGEL. 275 



attract attention by the contrast between their deep blue-black 

 colour and the pale silvery green of the Woolgarden Phyllites 

 beneath them. In the entrance to the Keep they are seen to be 

 sheared into numerous shear-lenticles, filled with broken greenish 

 rock and vein- quartz. 



Tintagel Haven and Barras Nose. 

 (See figs. 4 & 6, pp. 270 & 276.) 



The two series of beds seen in the eastern cliff of the Island 

 reappear at Barras Nose, and in a little ridge of rock from which a 

 boat is suspended on davits. Barras Nose is for the most part made 

 up of blue-black slate (Barras Nose Beds), often gritty, overlain by 

 typical sheared volcanic rock. The crag at the top of the headland 

 contains a band of sheared quartzitic and calcitic rock, banded with 

 veins of very pure magnetite crystallized in octahedra. This rich 

 band of iron-ore is, unfortunately, not extensive enough to work : 

 if it were of more widespread occurrence, it would form a valuable 

 ore. Similar magnetiferous bands of rock are seen in Treknow 

 Valley. On the south-east side of Barras Nose there is an escarp- 

 ment of the silvery-green "Woolgarden Phyllites, underlain by a 

 second band of lava. This second band continues along the top of 

 the little ridge from where the boat hangs (see fig. 6). This ridge, 

 however, is not entirely composed of volcanic rock, for the Barras 

 Nose Beds form the mainland side of it. The same blue-black 

 slate underlies the lava in the escarpment, and is also found in 

 front of the Hotel. 



The structure of Tintagel Haven is very complicated ; but the 

 "Woolgarden Phyllites certainly occur near the Tea-Rooms. Under 

 the Waterfall, Mr. W. M. Hutchings 1 found the volcanic rock ; but 

 the section was hidden by beach in 1908. This rock is a con- 

 tinuation of that seen at the bottom of the cliff below the Keep. 



Inland the Woolgarden Phyllites occur east of the Hotel, and 

 form the uppermost part of Smith's Cliff. Bosses of epidiorite have 

 intruded into them at several localities along this cliff. At the 

 base of Smith's Cliff the lava reappears, including two 5-foot bands 

 of blue -black slate. 



A small bay separating Smith's Cliff from Willapark is bounded 

 by steep cliffs entirely made up of lava; the blue-black slate 

 overlies the lava at Willapark and Smith's Cliff, and at the former 

 place the Tredorn Beds form the headland. Lye Bock and the 

 Bossiney Sisters also consist of the Tredorn Phyllites. 



Bossiney Bay. 



All the upper beds which formed the nose of the anticline have 

 been eroded away by the sea at this locality, and the Woolgarden 

 Phyllites occupy the range of magnificent cliffs between Trewethet 

 Gut and the Elephant Rock. At no other part of this coast are 



1 Geol. Mag. dec. iii, vol. vi (1889) pp. 53 & 101. 



