摘要
These inclusions occur in the quartz phenocrysts of the topazite porphyry inTaishun County of Zhejiang Province. The rock usually has a typically igneousporphyritic texture. Making up 20% of the whole volum, the phenocrysts are com-posed chiefly of the euhedral quartz 1-2 mm in diameter and occasionally of mica.The groundmass of the rock is fine-grained in texture, consisting essentially ofeuhedral-subhedral prismatic topaz （35%） and anhedral quartz （45%）. Thecomponents of the rock are:SiO<sub>2</sub> 79.89%, Al<sub>2</sub>O<sub>3</sub> 15.19%, Fe<sub>2</sub>O<sub>3</sub>, 0.36%, FeO 0.05%,
