porphyritic

• LAV-141 was drilled on Section 1000NE and intersected brecciated and porphyritic andesite cross-cut by dacite dykes. —  Marketwire - Breaking News Releases
• Whether it was granitic or porphyritic, I had no opportunity of examining, but incline to think it belonged to the latter Of the general features of the geological system of Corsica, an opportunity may occur for taking a short review. —  Rambles in the Islands of Corsica and Sardinia with Notices of their History, Antiquities, and Present Condition.
• He calls the porphyritic trap "dark granite." —  The Land of Midian — Volume 2
• These ruin-like rocks command the plain; they are composed of a coarse-grained granite, nearly porphyritic, the yellowish white feldspar crystals of which are more than an inch and a half long. —  Personal Narrative of Travels to the Equinoctial Regions of America, During the Year 1799-1804 — Volume 2
• The degradation of the rock on which this formation rests is constantly bringing down masses of it, and mingling them with the basaltic, porphyritic, granitic, and calcareous fragments which the torrents carry down to the valleys, and, through them, in a state of greater or less disintegration, to the sea. —  The Earth as Modified by Human Action

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