| 11. | Their matrix is heavily altered to clay while phenocrysts are mostly preserved.
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| 12. | The rocks contain phenocrysts of clinopyroxene, hornblende and plagioclase.
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| 13. | Feldspar phenocrysts typically are labradorite to andesine in composition.
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| 14. | Sanidine phenocrysts and augite ( or enstatite ) are found in some samples.
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| 15. | Basalt on Lake Island is characterized by abundant to labradorite and clinopyroxene phenocrysts.
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| 16. | Mineralogically the fine-grained phenocrysts consist of quartz, feldspars and biotite.
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| 17. | Plagioclase and, in lesser measure, clinopyroxene and olivine form its phenocrysts.
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| 18. | The andesitic lavas contain phenocrysts of andesine, hornblende, plagioclase and hypersthene.
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| 19. | It contains microcline, and few feldspar phenocrysts.
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| 20. | The distinctive texture of rapakivi granite is due to oligoclase rims on orthoclase phenocrysts.
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