The geology of Ascutney Mountain, Vermont . m; H <^. (B) THE MERIDEN GRAVURE CO. DALY] MAIN SYENITE STOCK. 63 Feldsijars of similar nature and size are abundant in the basicsegregations with which this phase is richly charged, and with themare granitic groupings of several individuals separated by interstitialquartz. The segregations are mostly composed of those minerals ofthe groundmass which crj^stallize out in an early stage of consolida-tion. The large feldspars and the groups would thus antedate thatgroundmass. The feldspar phenocrysts which are mantled with ortho-clase very often pres
The geology of Ascutney Mountain, Vermont . m; H <^. (B) THE MERIDEN GRAVURE CO. DALY] MAIN SYENITE STOCK. 63 Feldsijars of similar nature and size are abundant in the basicsegregations with which this phase is richly charged, and with themare granitic groupings of several individuals separated by interstitialquartz. The segregations are mostly composed of those minerals ofthe groundmass which crj^stallize out in an early stage of consolida-tion. The large feldspars and the groups would thus antedate thatgroundmass. The feldspar phenocrysts which are mantled with ortho-clase very often present the appearance of having been extensivelycorroded by the magma before the mantles grew about them. It isprobable, also, that there were two generations of the granitic groupings of large individuals suggest that the porphy-ritic structure may be largely due to protoclastic action breaking upa coarse-grained granitic rock already more or less completely solidi-fied in the conduit when the somewhat later magma of the ground-mass was
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