The rocks of its lower half are mainly granite and gneiss; its upper half is composed of porphyritic greenstone, and a variety of minerals occur. [Please select]
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Greenstone is an excellent rock, and has a fine surface, but it is unmanageable. [Please select]
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The Cumberland and Westmoreland hills are, in general, composed of clay-slate and gray-wacke, with occasional masses of chert[7] (like that which forms the summit of Scawfell), porphyritic greenstone, and syenite. [Please select]
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