41. The Lobster Creek Volcanics is actually an intrusion of plagioclase pyroxene hornblende porphyry from. 42. The mantle is made from glass, that partially devitrified into pyroxene and plagioclase . 43. Amphibole crystals are enclosed in intersitital plagioclase crystals and sometimes contain secondary biotite crystals. 44. Magma mixing and plagioclase crystallization occurred in it. 45. If more than 90 % plagioclase is present, then the rock is an anorthosite. 46. Porphyritic dacites contain blocky highly zoned plagioclase phenocrysts and / or rounded corroded quartz phenocrysts. 47. Their essential minerals are pyroxene, plagioclase and garnet : chemically they resemble the gabbros. 48. With an increase in calcic plagioclase and mafic minerals the rock type becomes a diorite. 49. However, microcline is commonly poikilitic, with abundant fine-grained plagioclase and quartz. 50. The Caolingshan Basalt consists of olivine and pyroxene, with crystals of biotite and plagioclase .
