This paper is the result of mineral exploration engineering.

Objective The Dongqiyishan fluorite deposit is a super−large fluorite deposit, which is related to alkali feldspar granite in the eastern section of the Beishan metallogenic belt. The orebodies are hosted in alkali feldspar granite, marble and andesite, which are controlled by NE−trending and NS−trending fault structures.

Methods Based on a study of the geological characteristics of Dongqiyishan fluorite deposit, this study investigated therare earth and trace element geochemistry of the fluorite and wall rocks in the fluorite deposit.

Results The trace elements curves in fluorites are consistent, and significantly enriched in high−temperature elements such as Bi, Cd and Mo relative to the crust values, indicating high−temperature mineralization and homology. Fluorites and alkali feldspar granites exhibit similar rare earth element geochemical characteristics. Y/Ho ratios of 10 fluorite samples range from 21.02 to 28.52, La/Ho ratios from 3.58 to 15.23. All samples fall within the hydrothermal region of Tb/La−Tb/Ca diagram. Sm/Nd ratios range from 0.26 to 0.42 for fluorite and from 0.30 to 0.33 for alkali feldspar granite. δEu values range from 0.60 to 0.64, with an average of 0.62, indicating a significant negative anomaly. δCe values range from 0.89 to 0.94, with an average of 0.91, indicating a weak negative anomaly.

Conclusions Combined with the geological characteristics of the deposit, it is proposed that the Dongqiyishan fluorite deposit is a magmatic−hydrothermal vein−type fluorite deposit, which is a product of the tungsten−tin−rare metal−fluorite mineralization system related to alkali feldspar granite in the area. The ore-forming fluid of Dongqiyishan fluorite deposit is mainly magmatic hydrothermal fluid, the ore-forming material F mainly comes from the deep alkali feldspar granite, and the Ca mainly comes from the marble strata.