| 31. | The dacites contain phenocrysts of biotite and large feldspar crystals embedded in an oxidized groundmass.
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| 32. | However, significant variations in the percentage of phenocrysts in the six domes prove otherwise.
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| 33. | Other basalts contain olivine and pyroxene phenocrysts.
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| 34. | Phenocrysts formed at depths of less than.
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| 35. | Biotite, hornblende, plagioclase and quartz form most of the phenocrysts in these layers.
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| 36. | Phenocrysts include olivine, plagioclase and pyroxene.
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| 37. | Phenocrysts include biotite, feldspar and quartz.
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| 38. | Phenocrysts are dominated by plagioclase; in the latter stages of activity biotite dominates over pyroxene.
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| 39. | Most magmas are a mixture of liquid rock ( melt ) and minerals ( phenocrysts ).
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| 40. | Phenocrysts contained in Mentolat's rocks include : clinopyroxene, olivine, orthopyroxene and plagioclase.
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