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封面故事：川西甲基卡变质岩系中的十字石。以其外形而得名的十字石是典型的中温-中压变质矿物, 常见于中-酸性侵入岩体的热接触变质带中。围绕甲基卡二云母花岗岩侵入穹窿, 形成了宽达10余千米的变质带。从接触带外展, 依次是十字石带、十字石-红柱石带、红柱石带和黑云母带。通过调查矿田新3号脉超大型锂矿床以及134号脉等大型锂矿床, 发现十字石-红柱石带是发育富锂伟晶岩的有利围岩。十字石-红柱石的矿物组合, 作为甲基卡锂矿床的赋存标志, 在川西其他地区寻找花岗伟晶岩型锂矿床中也取得了良好的找矿效果。这项由中国地质科学院矿产资源研究所杨岳清研究员等取得的研究成果, 详见本期第419-433页。（图片提供：杨岳清）
Cover Story：Staurolite in the Jiajika metamorphic rock series in the Western Sichuan Province. Staurolite, named for its shape, is a medium-temperature, medium- pressure metamorphic mineral commonly found in the outer thermal-contact metamorphic belt of intermediate acid-intrusive rocks. Surrounding the intrusion dome of the methyl calcimite granite in Jiajika, a metamorphic zone of more than 10 kilometers in width has been formed. Extending from the contact zone, this metamorphic zone is followed by staurolite, staurolite andalusite, andalusite, and biotite zones. Based on investigations of the super large lithium deposits of the new No. 3 vein and the large lithium deposits of the No. 134 vein, the staurolite andalusite belt was found to be a favorable wall rock for the formation of lithium pegmatite. As a prospecting indicator for the Jiajika lithium deposit, staurolite andalusite has played an effective role in the exploration of granite pegmatite type lithium deposits in other areas of western Sichuan. The research achievement was led by Professor YANG Yue-qing, Institute of Mineral Resources, CAGS. For details, see pp. 419-433 of this issue.(Photo by YANG Yue-qing)
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