Aldan Shield

The Aldan Shield is a shield in Siberia forming an exposed part of the basement of the Siberian Craton, and together with the Anabar Shield to its northwest it is one of the craton's main features. It lies across the southern end of the Sakha Republic and the eastern end of Irkutsk Oblast in Russia, exposing Archean basement rock with Proterozoic reworking in places, including granulites and rare minerals such as charoite, brookite, frankamenite, tausonite and yuksporite; the world's only known charoite deposit lies within the shield, at Sirenevyi Kamen, the Lilac Stone, in the Murun Massif.