The minerals of gabbros include olivine, plagioclase, clinopyroxene
and opaque mineral that altered to serpentine, amphibole, sericite and iron oxides.
5a), which could be explained by -20% clinopyroxene
fractionation from other West Valley magmas but at pressures much higher than would be expected for an incipient rift in thin crust (Cousens et al.
Mafic minerals (biotite and hastingsitic hornblende with rare clinopyroxene
inclusions) account for up to 10 vol% of the rock.
All five adzes are made of alkalic basalts containing olivine and clinopyroxene
phenocrysts up to ~1 mm in size.
In contrast, the moon's surface appears to have roughly equal mixtures of these two minerals and one other, clinopyroxene
Basalt is medium-grained, with ophitic texture formed by plagioclase and clinopyroxene
and matrix consisting of chlorite, zeolite, Ti-magnetite, titanite, ilmenite, apatite and pyrite.
Phenocrysts consist mostly of plagioclase and rarely, clinopyroxene
Tremolite schist consists mainly of tremolite-actinolite + calcic clinopyroxene
+ talc with minor plagioclase.
Within this prospect there are also platinum and palladium enriched magnetite - clinopyroxene
veins cutting the dunite.
The primary mineralogy of komatiites is simple: phenocrysts of olivine and spinel/chromite (+/pyroxene) are enclosed in a groundmass composed of glass, calcic clinopyroxene
and minor orthopyroxene.
It is here that eclogite forms consisting of red pyrope garnet and green clinopyroxene
Objectives of this study include: 1) determining mineral composition of olivine, clinopyroxene
, and orthopyroxene in the xenoliths; 2) examining individual chemical zoning characteristics or orthopyroxene, clinopyroxene
, and olivine; 3) comparing mineral chemistry and zoning differences between xenoliths from different eruption styles; and 4) use xenolith compositions to determine lithospheric mantle pressure and temperature.
phenocrysts are also zoned and plot on or near the diopside-augite boundary.
In a mine at the Jagersfontein, Haggerty and Sautter discovered two highly unusual rock fragments, containing numerous specks of the mineral clinopyroxene
scattered within garnet.
For example, the method estimating the crystallization temperature and pressure based on clinopyroxene