The garnet muscovite granitic pegmatite of Um Solimate, in southern Egypt, represents a promising asset for strategic and economic metals, especially Bi–Ni–Ag–Nb–Ta as well as U and Th. The ore bodies occur as large masses, pockets and/or veins of very coarse-grained pegmatites, which consist mainly of K-feldspar, quartz and albite with subordinate muscovite, garnet, and biotite. Radiometric data revealed that eU- and eTh-contents of the pegmatites reach up to 39 ppm and 82 ppm, respectively. The studied pegmatites are enriched in primary U and Th minerals (uraninite, coffinite, thorianite and uranothorite) as well as Hf-rich zircon and monazite, which give rise to anomalous radioactive zones. Niobium-tantalium-bearing minerals (i.e. ferrocolumbite, microlite and uranopyrochlore), xenotime, barite, galena, fluorite, and apatite are ubiquitous, and, consequently, the studied pegmatites belong tothe Niobium–Yttrium–Fluorine-type (NYF) family. The noble metal mineralization includes argentite (Ag₂S), native Ni and Bi as well as bismite and bismoclite. In addition, beryl and tourmaline are observed in pegmatites near the contact with metasediments and ultramafic bodies. The observed compositional variations of Ta/(Ta+Nb) and Mn/(Mn+Fe) ratios in columbite (0.08–0.45 and 0.11–0.57, respectively) and Hf contents in zircon (3.54–6.46 wt%) may reflectan extreme degree of magmatic fractionation leading to formation of the pegmatite orebody.

中文翻译：

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埃及东南沙漠 Um Solimate 稀有金属 (NYF) 伟晶岩中含铀和钍矿物的地质和矿物化学

位于埃及南部 Um Solimate 的石榴石白云母花岗岩伟晶岩是战略和经济金属的有前途的资产，尤其是 Bi-Ni-Ag-Nb-Ta 以及 U 和 Th。矿体以大块、矿穴和/或极粗粒伟晶岩的矿脉形式出现，主要由钾长石、石英和钠长石组成，其次是白云母、石榴石和黑云母。辐射测量数据显示伟晶岩的 eU 和 eTh 含量分别高达 39 ppm 和 82 ppm。所研究的伟晶岩富含原生 U 和 Th 矿物（铀矿、铜镍矿、钍矿和铀钠辉石）以及富含 Hf 的锆石和独居石，从而产生异常放射性带。含铌钽的矿物（即铌铁矿、微晶石和铀辉绿石）、磷钇矿、重晶石、方铅矿、萤石和磷灰石无处不在，并且，因此，所研究的伟晶岩属于铌-钇-氟型（NYF）家族。贵金属矿化包括银矿（Ag₂ S)、原生镍和铋以及铋矿和铋矿。此外，在与变质沉积物和超镁铁质体接触的伟晶岩中观察到绿柱石和电气石。观察到的铌铁矿中 Ta/(Ta+Nb) 和 Mn/(Mn+Fe) 比（分别为 0.08-0.45 和 0.11-0.57）和锆石中 Hf 含量（3.54-6.46 wt%）的成分变化可能反映了极端程度岩浆分馏导致伟晶岩矿体的形成。