Abstract A new technique for the complete dissolution of cassiterite, which makes it possible to determine the age of this mineral by U–Pb isotope dilution (ID-TIMS), has been developed and applied. This method allows a significant improvement in the accuracy of determining the age and expansion of the range of objects that can provide direct information about the age of tin ore deposits. The high-precision age of cassiterite (1539.5 ± 0.9 Ma) from the Pitkäranta tin deposit in the North Ladoga region proves that the formation of the tin ore deposits is genetically associated with the intrusion of rapakivi granites of the Salmi massif.

中文翻译：

---

以 Pitkäranta 锡矿床为例，对锡石进行 ID-TIMS U-Pb 测年的新方法

摘要 开发并应用了一种锡石完全溶解的新技术，可以通过 U-Pb 同位素稀释法 (ID-TIMS) 确定该矿物的年龄。这种方法可以显着提高确定年龄的准确性，并扩大可以提供有关锡矿床年龄的直接信息的对象范围。来自北拉多加地区 Pitkäranta 锡矿床的锡石高精度年龄 (1539.5 ± 0.9 Ma) 证明锡矿床的形成与 Salmi 地块的 rapakivi 花岗岩的侵入在遗传上有关。