Peralkaline granites and pegmatites are a prime repository of REE and HFSE, critical raw materials. Although it is accepted that magmatic processes are fundamental in concentrating these metals, the role of hydrothermal fluids in concentrating and fractionating these elements remains unclear. This paper investigates the global reproducibility of the magmatic-hydrothermal evolution of alkaline silica-saturated systems using alkali pyroxene and amphiboles from six alkaline complexes. These minerals contain significant amounts of REE and other HFSE, and pyroxene is stable throughout the magmatic and hydrothermal stages. Amphibole consists of mostly unzoned arfvedsonite, leakeite, and katophorite, while pyroxene is always aegirine. Two types of aegirine were defined. In all complexes, type-I aegirine is zoned; its core is enriched in Ca, REE, Zr, Hf, Sc and Sn, and the rims in Na, Fe3+ and contains secondary rare-metal bearing minerals and fluid inclusions. Type-II aegirine replaces amphibole and is oscillatory zoned. We interpret the amphiboles and REE-rich cores of type-I aegirine to have grown during the magmatic stage, whereas the rims of REE-poorer type-I and II aegirine are formed during the hydrothermal stage. During magmatic crystallization, REE intake into amphiboles and pyroxene as well as LREE-HREE fractionation were favored by their crystallographic properties and by competition among them and other minerals. During subsequent hydrothermal stages, REE and other HFSE were remobilized, locally reconcentrated and fractionated in mineral pseudomorphs and secondary pyroxene. These observations point out the importance of studying rock-forming minerals such as pyroxenes and amphiboles to unravel geological events controlled by common processes globally.

中文翻译：

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碱性辉石和闪石：通过过碱性花岗岩系统的岩浆-热液转变了解稀土元素和其他高场强元素行为的窗口

高碱性花岗岩和伟晶岩是关键原材料 REE 和 HFSE 的主要储存库。尽管人们普遍认为岩浆过程是浓缩这些金属的基础，但热液流体在浓缩和分馏这些元素中的作用仍不清楚。本文研究了使用碱性辉石和来自六种碱性复合物的角闪石的碱性二氧化硅饱和系统的岩浆-热液演化的全局可重复性。这些矿物含有大量的 REE 和其他 HFSE，辉石在整个岩浆和热液阶段都是稳定的。角闪石主要由未分区的阿弗维森石、漏闪石和钾闪石组成，而辉石始终是绿闪石。定义了两种类型的aegirine。在所有的复合体中，I 型 aegirine 被划定；其核心富含Ca、REE、Zr、Hf，Sc 和 Sn，边缘为 Na、Fe3+，并含有次生含稀有金属的矿物和流体包裹体。II 型 aegirine 取代闪石并且是振荡分区。我们将 I 型 aegirine 的角闪石和富含 REE 的核解释为在岩浆阶段生长，而 REE 贫乏的 I 型和 II 型 aegirine 的边缘是在热液阶段形成的。在岩浆结晶过程中，REE 进入角闪石和辉石以及 LREE-HREE 分馏因其晶体学特性以及它们与其他矿物之间的竞争而受到青睐。在随后的热液阶段，REE 和其他 HFSE 被再迁移、局部再浓缩和分馏为矿物假晶质和次生辉石。