Changes and ore-forming significance of calcium and fluoride in Gannan Xintang fluorite mining area

Gannan is one of the most important areas of high quality fluorite in China.The systematic analysis on the calcium and fluorine ions of groundwater in Xintang fluorite mining area can not only reveal the properties of the mine itself,but also be important for the exploring of new mine areas.Our study results indicated that the ion contents of calcium and fluorine had obviously different spatial distribution.The abundance of calcium and fluorine in the groundwater of deposits and around was much higher,compared to that in the underground water 2 kilometers away from the deposit.The former's figure was almost ten times the latter's.The analysis also showed that the contents of calcium have a higher correlation with that of fluorine in the groundwater.The paper revealed that the fluorite was mineralized by calcium and fluorine produced in the process that hydrothermal circulation incessantly leached the wall crack.Hence fluorite mineralization was determined by calcium and fluorine,and was closely related with the groundwater activity in this area as well.We finally reached the conclusion that the abnormal changes of calcium and fluorine could be used as an important indicator for exploring orgs.