Cassiterite U - Pb Isotope Age o f Tin Ore North Langsong Deposit Tanky Area, Nghean, Vietnam

The North Langsong tin deposits are located in Tanhop commune, Tanky district, Nghean, and belong to the Phuhoat uplifted structure. This is the biggest tin ore area in the Northern and Central region of Vietnam. Tin accompanies quartz veins in the northeast - southwest fault zone, developed in carbonate rock formations. The main ore components include pyrite, arsenopyrite, cassiterite, and less commonly galena, chalcopyrite, magnetite, and secondary minerals such as limonite, goethite, and psilomelan. Authors used the results of LA - ICP - MS U - Pb cassiterite analysis to interpret the relationship between tin mineralization and granitoid intrusion. U - Pb analysis of cassiterite from the North Langsong tin deposits yielded isotopic ratios of 207Pb/206Pb - 238U/206Pb ranging from 0.0000 to 1.2947 and from 0.0049 to 0.3626, with an age of 35.1 ± 5.2 Ma. On that basis, the authors conclude that the North Langsong ore deposits are associated with young (Paleogene) magmatic activity, represented here by granitoid rocks of the Ban Chieng complex.