Pigeonite is named for its type locality on Lake Superior's shores at Pigeon Point, Minnesota, United States.
12.
It forms complete solid solution series with hedenbergite ( FeCaSi 2 O 6 ) and augite, and partial solid solutions with orthopyroxene and pigeonite.
13.
Slow cooling allots the calcium the necessary time to separate itself from the structure to form exsolution lamellae of calcic clinopyroxene, leaving no pigeonite present.
14.
Component chemicals found at Lascar include : anorthite, augite bordering on diopside, bronzite, fassaite, forsterite, hypersthene, pigeonite, and more.
15.
Primary ( magmatic ) mineral species also encountered in komatiites include olivine, the pyroxenes augite, pigeonite and bronzite, plagioclase, chromite, ilmenite and rarely pargasitic amphibole.
16.
Other silicates were detected as well, such as the Magnesium-rich end-member of olivine called forsterite, pigeonite, plagioclase, augite, clinopyroxene, and orthopyroxene.
17.
The groundmass contains interstitial quartz or tridymite or cristobalite . " Olivine tholeiite " has augite and orthopyroxene or pigeonite with abundant olivine, but olivine may have rims of pyroxene and is unlikely to be present in the groundmass.
18.
The low-temperature limit of pigeonite stability depends upon the Fe / Mg ratio in the mineral and is hotter for more Mg-rich compositions; for a Fe / Mg ratio of about 1, the temperature is about 900 �C . The presence of pigeonite in an igneous rock thus provides evidence for the crystallization temperature of the magma, and hence indirectly for the water content of that magma.
19.
The low-temperature limit of pigeonite stability depends upon the Fe / Mg ratio in the mineral and is hotter for more Mg-rich compositions; for a Fe / Mg ratio of about 1, the temperature is about 900 �C . The presence of pigeonite in an igneous rock thus provides evidence for the crystallization temperature of the magma, and hence indirectly for the water content of that magma.
