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Abstract
Several uraukun occurrences have been discovered in VtH10llS localities ill the Eg)’Plian terrains. These include iuaiuly the different uranium mineralizatious associated with younger granites of the basemeut rocks in (be Ea tern Desert 01’ else those associated with the edimti’lllary
arboniferous rocks o f the Um Bu na F ormation in West Celitre l Sinai, Amcng the uraWlIiJ) uuaemlizations of the former type. tll<11 OCCUlTil\g ttl Gabal Gaflar youllger granite pMon at abour 40 kill ;W Hurghada ity is greatly promising dne (0 irs relalively wide distrfbnrion ill a number of occurrences. The latter have been eanumerared nom (J[ 10 GXIJI which are hosted in the younger granite itself except G\’ oceurrence which is hosted in El Hanunamat sediments which oc urs ar the northwestern contact oCQ. Gartar granite phuou. Inreresr ofG\’ occurrence is due 10 the presence of rare eartb’s mineralization besides that of uranium.
The your er granites of G. Gattsr ore pink to reddish pink in color, medium to coarse grained and consist lOOillly of quartz. potash feldspar plagioclase And uuno r ammmt of biotite. According to lUIuy authors the age assigned to these grauites rang fronl48’1 10 5 9 Ma.On the other band, £1 Hammamat sediment are slig1Jtly metamorphosed aud con iSI e entially of conglomerate . sill tones sud greywackes and are iererbedded wilb volcanic rocks (Dokhan volcanics). TIle coaglomerates comaia uumeious c!MIS oftlle pre-existing roc •S. An age of 585 ± 15 13 II.’s been assigned to EI Hal1lilla.mat SedUI1i1:111S which 81’e actually intmded wirlt the younger granites. According [0 R”,,(J.), the uranium occurrences of G. Gatror area how obvious po uuagmaiic hydrothermal alteration features that have affected both lbe grauite and El-Hannaamat sediment along (heir contact 20n”” Ill! most common fealUl’lI exhibited by the granite include alkali metasomatisui, silicfication, bemaritziation kaolsnzation besides fluoritizarion aed potty or dendrirjc Jl1,1J1gauese oxide Tbe llydrOlbe.nnal aheraricns associated with El-Heuansunt sediment are Ilch.tally represemed tty h:unatitjzatioll, :tluoritizatiou, repidotization, chloritization and deudutic mangnnese oxides. III addilioll, bleaching (chemical reduct iou of •• -on) by hydrothermal solution bas affected some zones ”,ithiLI EI Harlunllm”t rocks; iI matter which rums the if colors fiom ucnual dark green or black 10 creamy yello\ colors,
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iinerlllogk”lly. tile ureuiem llIinemliza~ioll’ <’$Seiltl”l[y manifesred ill the form of secondary 11l’a1UUm minerals with uranophaue (iliCl\te) as rhe mosr abundant. However the primary mineral ur!lninir~ {UOi) bas been identified ill or occurrence and several Sl!C01WIlI)’ uranium minerals have also been identified in rhe mineralized auite occurrences bill in minor amouuts (Sayyah lind Anawawiye, 1990PJ. The letter involved soddyire (silicate. umohoite (ll1ol)~date). becquerelite (hydrated oxide). clalkeriie,zippeite (sulfate) and kasolite (silicale). In EI Hauanamat G’ occurrence. uranophane has also been idemifiesd as the main secondary uranium nJellit:11 besides minor tuyuamnuite (vanildate) as found by Mahdy et al 1990)0) aild
chroeckingerite (carbouate) as indicated by Daboor(l9g6i~). On the other hand, the REEs present in G occurrence are not mluwested in the form of any corresponding RE mineral. As a matter of fact. it is knov 11 that while more than 200 minerals are known in uarure in which tbe REEs exceed 0.0 1%. QlIly :lOO\lt <l dozen of these minerals 1]:IIlt occur ill ”uffi,ien,I rouaages 10 be considered <l resources fur couunercial processing, However. ~OOIl\ 95% of REEs O,CUI in ollly 3 minerals; viz monazite, bastuasire OIl<! xeuorime which govern the proce sing techniques of REBs. III the meanrime, ion adsorption ores ’would 00 funned by mineral weathering where till! RE cations would be released and inigrate downwards 10 be adsorbed by a hnninosilicare uiinerals like kaoliu as is manifested in Long. all, Yianxi at south China,
Se\’erallJydrouretalh.ltgkal processes have Il,CIl\aUy beeo de~”’lOiled for the preparation <:If markerable uranium and rare earth products, The processes depend priJl:IllJ’lIy on the Ore composjrion 011~ and gangue minerals), ore grade and volume besides its physical properties, HydJ’oJuetallllrgical processes involve’ indeed two main operations, viz ors leaching in which the required metal value (8) is put into suitable ,1qU!!mIS solutiou followed by ils recovery from
1\11i0I1 ill the 100.1 pOS$ible pure fom}, The latter juvolvE’s llIrnnly oIvellr extractiou and ion exchange techniques ..
However, given the relatively low assay of uranium and the relatively limited extension of G. Gattar occurrences, i~ was found greatly advaarageous 10 study the poieutiality of dire” solvent leaching of G. Gatrnr ore materials. TIri technique i actually justified by its relatively low capital expenditures.
FOT rbis purpose. Gil and G umuiiuu occurrences (If G. Gauar area have been chosen for the present work. This first occurrence of GIl belor ro tbe vein-type b>’lIrolllemJalll’lilleraliZlltioll
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