Gabal El Fereyid area, represents a promising area for monzogranite and pegmatites hosted rare-metal mineralization. Microscopically, monzogranite and pegmatites consist of K-feldspar, albite, and quartz with few biotite +/– hornblende. The radiometric studies of anomalous pegmatite samples show that their eU-contents reached up to 149 ppm while their eTh-contents reached up to 375 ppm, in contrast the eU and eTh contents of monzogranite range from 1 to 5.7 ppm and from 4.2 to 29.1 ppm, respectively. This indicates strong post-magmatic U-enrichment in the pegmatitic melt, due to the presence of radioactive minerals as thorite, uranothorite, fergusonite, samarskite and ishikawit. U and Th mineralization in pegmatites are discriminated as hydrothermal and magmatic types. Pegmatites show enrichment of large ion lithophile elements (LILE; Pb and Rb,), high field strength elements (HFSE; Y, Zr, Th, U, Nb and Ta) and rare earth elements but depleted in K, P, Sr, Cs, Ba and Ti. Pegmatites indicate moderate to large negative Eu anomaly and show clear W-type tetrad effect of the REE.

中文翻译：

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埃及东南沙漠 Gabal El Fereyid 花岗岩中伟晶岩的稀有金属分布及成矿潜力

Gabal El Fereyid 地区是二长花岗岩和伟晶岩稀有金属矿化的有前途的地区。从微观上看，二长花岗岩和伟晶岩由钾长石、钠长石和石英组成，很少有黑云母+/-角闪石。异常伟晶岩样品的放射学研究表明，它们的 eU 含量高达 149 ppm，而其 eTh 含量高达 375 ppm，而二长花岗岩的 eU 和 eTh 含量则分别为 1 至 5.7 ppm 和 4.2 至 29.1 ppm ， 分别。这表明伟晶岩熔体中存在强烈的岩浆后 U 富集，这是由于存在放射性矿物，如钍长石、铀钠长石、镁钛矿、铁锌矿和石卡威。伟晶岩中的 U 和 Th 矿化被区分为热液和岩浆类型。伟晶岩显示富集大离子亲石元素（LILE；Pb 和 Rb，），高场强元素（HFSE；Y、Zr、Th、U、Nb 和 Ta）和稀土元素，但缺乏 K、P、Sr、Cs、Ba 和 Ti。伟晶岩表明中到大的 Eu 负异常，并显示出明显的 REE 的 W 型四分体效应。