Page:Transactions of the Geological Society, 1st series, vol. 1.djvu/305

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3. From Rona.

a. Compact epidote of a bright yellowish-green colour, forming slender veins which traverse a rock principally composed of flesh-red felspar and a little grey quartz. It is very similar to that from Iona, except that this contains less quartz.

b. A rock composed of hornblende and reddish felspar, together with epidote, both as a constituent part and in veins passing through the rock.

These two specimens, and particularly the first, are nearly identical with some of the varieties from Malvern.

c. Compact epidote in small threads passing through vitreous quartz.

Dr. Wollaston, who had the goodness to compare, at my request, the above specimens from the Western Islands, with those I brought from Malvern, has since found the epidote in similar circumstances, in the Islands of Guernsey and Jersey; and he has been so kind as give me some of the specimens he collected. They are as follow:

a. A granular rock, composed of yellowish-green compact epidote and hornblende, in small grains. It is nearly the same as that which I found on the northern face of the End-hill; the only difference is, that this specimen from Guernsey contains a greater proportion of epidote.

b. This so exactly resembles the specimen a from Rona, that they might be considered as portions of the same mass.

c. Granite consisting of reddish felspar, white quartz and a little greenish-black mica, including a mass of epidote crystallized in slender divergent prisms. This specimen is from jersey.

§ 22. On the summit of the ridge which connects the End-hill with the North-hill, there is a rock almost wholly made up of hornblende,