The Study On "Snowflake Floc" Of Jadeitites In Myanmar And Discussion Of Evolution Process

With the improvement of living standards,people's demand for high-quality jadeite has gradually increased.The floc in high quality jadeite is one of the important factors affecting the latter's appearance and value.In recent years,a kind of characteristic "Snowflake Floc",the inclusion of jadeite in the shape of snowflakes,often appears in high quality jadeite,which is quite different from the common silk-like cotton floss in low quality jadeite."Snowflake Floc",with its snow-like shape and quite artistic conception,is considered to be typical representative characteristics of Myanmar "Muna" mine output,and is the characteristics of high-quality jadeite.As a result,"Muna Snowflake Floc" has become a category that has a positive impact on the price of jadeite.Many traders have used it as a gimmick to drive up prices,bringing certain chaos to the jadeite market.In this paper,jadeite samples containing characteristic "Snowflake Floc" are selected to have a test and analyze for the first time.By means of conventional gemological testing and modern testing techniques such as infra-red spectroscopy,laser Raman and electron probe,the structure,mineral composition and spectroscopic characteristics of jadeite are analyzed and studied.By comparing with the common cluster floc in jadeite,the main components,origin and evolution process of "Snowflake Floc" in jadeite are deeply analyzed and discussed,and the following main conclusions and understandings are drawn.1.The refractive index,density and points hardness of jadeite with characteristic "Snowflake Floc" are lower than that of common jadeite,which indicates that "Snowflake Floc" is different from that of jadeite in physical phase,and the morphology of "Snowflake Floc" is different from that of common round floc by naked eye observation.2.Through petrographic analysis and modern instrument testing,it is found that the main mineral component of "Snowflake Floc" is albite but with relatively high content of Ca in some parts,which is albite containing Ca,i.e.Ordovicite.3.Microscopically,it was found that "Snowflake Floc" is a sugar-granular or platelike aggregate formed by xenomorphic granular albite and there are a large number of islandlike jadeite remnants in it;jadeite particles have irregular edges,the matrix of jadeite is mostly fine-grained mylonization or fine-grained recrystallization structure,and high-angle suture lines structure and irregular edges exist between particles.4.A comprehensive study on the origin of "Snowflake Floc" is presumed: in the late stage of jadeite-to-jade formation,with the further dynamic recrystallization of jadeite minerals,the metamorphic fluids become rich in Si and poor in Al.Under the suitable geological environment of temperature and pressure,albite precipitates in the form of dispersed cotton aggregates and distributes relatively evenly in dynamically recrystallized jadeite minerals,thus forming a jadeite mineral “Snowflake Floc".This also leads the formation of "Snowflake Floc" to happen basically in the high-quality jadeite above the icelike field.5.The appearance of "Snowflake Floc" in high quality jadeite is not really characterized by the high quality mentioned in the market.On the contrary,the appearance of much "Snowflake Floc" will increase the content of albite in jadeite,and the appearance of excessive albite will affect the quality of jadeite instead.Therefore,the excessive emphasis on "Snowflake Floc" is only hype,and its value should be correctly measured.