Abstract: The Longping fluorite deposit is the large single fluorite deposit discovered in southern Jiangxi Province, China. The ore
body occurs in the NE-trending silicified fractured zone within the outer contact zone of the Yongfeng complex. In this paper, for the
first time, the Sm-Nd Isochronal method is used to estimate the age of Longping fluorite deposit, and rare earth elements and the
mineral composition of biotite in the Yongfeng complex are systematically studied. The ore-forming age of the Longping fluorite deposit
is 158 ± 3Ma, which is consistent with the diagenetic age of the Yongfeng complex, indicating that the Yanshanian fluorite
mineralization in this area was closely related to the Late Jurassic magmatism. The fluorite in the Longping fluorite deposit is enriched
in light rare earth elements, and the heavy rare earth elements remain relatively unchanged, with weak Ce positive anomalies (δCe=
1.08-1.11, average 1.09) and weak Eu negative anomalies (δEu=0.91-0.98, average 0.95), indicating that the ore-forming fluids of the
fluorite deposit experienced relatively high temperature. The results of electron probe analysis of biotite show that the Yongfeng complex was formed in a relatively high temperature, low pressure, and high oxygen fugacity environment. The magma originated from
the ancient crustal materials and the hydrothermal fluid was rich in F and other volatiles after the magma phase. The Longping fluorite
deposit may have mineralized in the Late Jurassic, and the genetic type is hydrothermal filling after the magmatism

Key words: Longping fluorite deposit, Sm-Nd dating, electron probe of biotite, genesis of deposit