| Like zircon, quartz, plagioclase, biotite and hornblende, major phenocryst phases, also show variable resorbtion effects. |
| Thus, during laser ablation, the laser beam may penetrate below the thin glassy surface of a grain into small inclusions or phenocryst phases. |
| The most common phenocryst silicate phases are olivine, plagioclase and augite, typically, although not always, appearing in that order. |
| The most important criterion is the phenocryst species, followed by the groundmass mineralogy. |
| A bleb of glass with clinopyroxene and plagioclase is located below and to the right of the large plagioclase phenocryst. |
| Thus the order of phenocryst appearance in Kilauea lavas is olivine, plagioclase, augite whereas in Mauna Loa lavas it is olivine, augite, plagioclase. |
