Experimental study on the co-occurrences of spodumene and lepidolite in granitic-class lithium deposits
Lithium is a rare metal element.Spodumene and lepidolite are the most important hard-rock type lithium minerals.It is of great significance to explore their co-occurrences and conditions to reveal the occurrence mechanism of lithium elements in different lithium ore minerals and the formation mechanism of lithium deposits.In this paper,in-situ observation crystallization experiments of spodumene-lepidolite-H2O system were carried out by hydrothermal diamond anvil cell.The 10 groups of experimental products are spodumene and muscovite.The crystallization conditions of spodumene are concentrated in 500～780℃,350～1300MPa,and the crystallization conditions of muscovite are concentrated in 440～710℃,180～1100MPa.Combined with the crystallization conditions of lepidolite(500～650℃,100～450MPa)obtained by previous experiments,and the Raman line scan results of the experimental product mica,the following understanding can be obtained:The crystallization temperature and pressure conditions of spodumene and muscovite have a high degree of overlap,which is consistent with the phenomenon that spodumene and muscovite can widely coexist in pegmatite;The crystallization of spodumene and lepidolite is mainly affected by pressure,and the influence of temperature and F content in the system is secondary;The petalite and lepidolite are formed under similar temperature and pressure conditions,but the content of F in the system influences the production of lepidolite and petalite;In the Li-rich system,the transformation from muscovite to lepidolite can occur with the decrease of pressure,indicating that the lepidolite edge of muscovite in nature may be formed in the process of melt or hydrothermal crystallization,not necessarily the result of hydrothermal alteration.
SpodumeneLepidoliteHydrothermal diamond-anvil cellTemperature and pressure conditionsPegmatite
万方数据
维普
