Beryl occurs in the ancient Roman mines at Wadi Nugrus, South Eastern Desert of Egypt. It ranges from small crystals to 10 mm in size, and it varies in color, appearing as bright green, pale green, dark green and brown-green with biotite inclusions. The trace and minor elements were analyzed by the SIMS method. The two rims are richer in Cs, Na, Mg, Fe, Sc, V, Rb and H2O than cores but are poor in Mn, Ca, Co, Sr and Li. The bright-green rim is richer than the pale-green one in Na, P, K, Ca, Fe, Rb, Cs and F, but poorer in Mg and Li. The alkaline elements (Cs, Na, Rb) and Fe correlate with the color zoning, and where beryl crystals have a maximum of these elements, the green color is strong and bright. The emerald of Wadi Nugrus has similarities with the geological setting of the Canadian emeralds. Emeralds occur along the contact zone between biotite schists, pegmatites and quartz veins. A large-scale interaction between Be-bearing magmatic fluids from granites and related pegmatites took place with hydrothermal fluids enriched in Cr, V, Sc, Mg and Ca after percolation through pre-existing serpentinite and talc carbonates, metagabbros and biotite schists and additional fluids bearing H2O, NaCl and CO2.

and REEs, and semi-precious colored gemstones such as topaz, beryl and tourmaline (Černý et al., 2012). Furthermore, they also represent the main sources of feldspar, which is used in the ceramics, glass and electronics industries. Pegmatites occur as sharply bounded homogeneous to zoned bodies within igneous or metamorphic host rocks. The current classification scheme uses some of these indicators to group granite pegmatites into five classes: abyssal, muscovite, muscovite-rare element, rare-element, and miarolitic (Černý, 1991; Černý and Ercit, 2005). This scheme is widely accepted, although some researchers have noted a greater diversity in pegmatites and pegmatite gneisses as well as a lack of correlation between depth and geochemistry (Simmons and Webber, 2008). For example, pegmatites in the rareelement class can be grouped into two families based on the principal rare-elements present. Firstly, Lithium-Cesium-Tantalum (LCT) pegmatite, which is identified as a diagnostic association, associated with S-type granites, that can be derived from mature sedimentary sources, for example marine shales. Pegmatites of this type can contain higher concentrations of Li, Rb, Cs, Be, Nb Ta, and Sn, as well as fluxing components such as P, F and B, as reported by Stilling et al. (2006), Simmons et al. (2016 and Liu et al. (2019). Other studies showed that the second Niobium-Yttrium-Fluorine (NYF) association can be used as a trace element signature (Černý and Ercit, 2005;Černý et al., 2012). Normally, NYF family pegmatites show a strong affiliation with A-type (anorogenic environment, lower continental crust ± mantle source) granitic magmas. In an orogen, NYF pegmatites can be spatially close to some Itype (igneous source) granites but they do not show any genetic link. The possibility that I-type magmas can produce NYF pegmatites is very low (Černý et al., 2012). NYF-pegmatites are enriched in Y, REE, Ti, Zr, Nb, Ta, U, Th, and F (Černý, 1991). In addition, a mixed LCT + NYF type, represented in pegmatites with intermediate geochemical signatures, has also been recognized (Černý

The monzogranite of El Fereyid is one of the rare metal-rich granites, where zircon is one of the ore minerals. Thus, studying zircon here is of vital importance. Most of the studied zircon grains are metamict and thus the loss of radiogenic Pb is detected for them. Nevertheless, our study allowed us to obtain the U-Pb (SHRIMP-II) age of magmatic crystallization for the El Fereyid monzogranite: 626 ± 13 Ma. These data allowed the correction of earlier determined age (K-Ar system in biotite) for the El Fereyid massif.Zircon grains of El Fereyid monzogranite demonstrate heterogeneous structure in CL images, they are rich in rare earth elements (REE, concentration 3000-22500 ppm), trace elements (U: 2000-14800 ppm, Th: 300-2500 ppm), and has low Th/U ratios (average 0.18). Most zircon grains exhibit multiple internal oscillatory zoning in CL images, indicating a typical magmatic origin. The core of zircon grain has a dark tone on CL imaging and magmatic-type REE spectra. Zircon cores are enriched in REEs, U, Th, and Y, thus recording that the magma was rich in incompatible elements. Light CL rims of zircon grains are depleted, relative to the cores in most of the trace elements, except for P, Ca, and Ti. REE spectra in rims show similar patterns that are more often demonstrated by hydrothermal zircon grains. This explains their crystallization in the late-magmatic stage when magma was rich in fluids but depleted in most of the trace elements.