The Origin of Iridescent Plagioclase from Finland
详细信息
- 责任者：Wang Chenbo (Beijing University of Science and Technology ; Beijing 100083 ; China) ; Chen Tingli
- 刊名：Acta Petrologica et Mineralogica
- 出版年：2011
- 卷期：30(1)
- 关键词：晕长石 ; peristerite ; 宝石 ; gems
- 页码：p.150-160
- 图表：9 illus., 1 table, 13 refs.
- 分类号：0700
- 出版序号：20120126
- issnNo：ISSN1000-6524
- isbnNo：CN11-1966/P
摘要
Macroscopic and microcosmic observations of the plagioclases from plagioclasite of southern Finland indicate that the plagioclases with parallel needle-like inclusions has iridescence, while the plagioclases without inclusions do not have iridescence. A compositional analysis by means of scanning electron microscope, electron microprobe and laser Raman spectrometry shows that the inclusions are magnetite in composition, and the plagioclases with or without inclusions have the same composition. It is suggested that the composition of the plagioclase and inclusions and the twin of the plagioclases are not the causes for the iridescence of the plagioclases, and the parallel distribution of the needle-like opaque inclusions in the plagioclase seems to be the factor responsible for the iridescent plagioclase.