Advances and general characteristics of the amazonite granite and related rubidium deposits in Central Asian Orogenic Belt.

Rubidium (Rb) is regarded as one of the most economically important of the "critical metals", and it is anticipated to be of the focus of international natural resource competition in the future. Although potential Rb resources are abundant in China, they predominantly occur in low-grade granite-hosted deposits that are difficult to exploit. High-grade pegmatite-hosted Rb deposits in which zinnwaldite, lepidolite, and pollucite occur as ore minerals are limited. Characterizing the processes that form Rb mineralization in Rbrich granites and related deposits, the differentiation of metallogenic elements, and the factors controlling occurrence state of Rb in different minerals is, therefore, crucial to understanding the metallogenic mechanism and development of robust prospecting models for Rb deposits. On the base of reviews on research advances in granite- and pegmatite-type Rb deposits, this contribution focuses on principal characters, temporal and spatcial distribution of amazonite granites and related Rb deposits in western and eastern segment of Central Asian Orogenic Belt (CAOB). Meanwhile, this contribution also gives research prospects in magmatism and mineralization geochronology, mineralization processes from magma to hydrothermal, and possible formation processes on high grade orebodies. It is proposed that CAOB contains majority of amazonite granites and related Rb deposits in the world. Amazonite granites and related Rb deposits from the western of CAOB are accumulated mainly in Triassic related to tectonic regime transformation from the Paleo-Asian Oceanic tectonic domain to Paleo-Tethys Ocenanic tectonic domain, while from the eastern of the CAOB they are accumulated in Late Jurassic to Early Cretaceous related to tectonic regime transformation from the Paleo-Asian Ocean tectonic domain to Paleo-Pacific Ocean tectonic domain. The Triassic and Late-Jurassic to Early Cretaceous are two critical periods for amazonite granitic magmatism and Rb mineralization for the western and eastern CAOB repectively, and deserve further studies especially on geochronology, petrology, and metallogeny.