The document discusses the geochemical exploration and evolution of the Rodruin Au-Zn prospect area in the Golden Triangle of Egypt, highlighting ancient mining practices and the geological features associated with gold and zinc mineralization. It identifies five mineralized zones, each with varying gold grades, and emphasizes the significance of trace element zoning and geochemical surveys in detecting mineralization in weathered bedrock. The study concludes that these surveys are effective tools for exploring stratiform Zn-Pb-Ag and structurally controlled Au and Cu mineralization in arid environments.

1. Harraz, H.Z; Hamdy, M. M.; Aly, S.A. and Abd Ella, S.A. (2020). Geochemical Exploration and
Evolution of Rodruin Au-Zn(±Pb±Ag) Prospected Area in the Golden Triangle–Egypt. The
Eleventh International Symposium On Geophysics, Isg-11, Faculty of Science, Tanta
University, (Abstract).
Geochemical Exploration and Evolution of Rodruin Au-Zn(±Pb±Ag)
Prospected Area in the Golden Triangle -Egypt
Hassan Z. Harraz; Mohamed M. Hamdy; Samir M. Aly; Samar A. Abd Ella
Geology Department, Faculty of Science, Tanta University, Tanta 31527, Egypt
The Rodruin prospect (Au-(Zn)) in the Golden Triangle –Egypt (26o
21/
59//
N, 33o
20/
32//
in the
Central Eastern Desert of Egypt, approximately 450 km to the south-southeast of Cairo) has been
exploited by the Ancient Egyptian Miners for a long time. The high grade gold mineralization was
mined from gossanous gold-bearing quartz veins; with the workings typically targeting structural
or shear zones, which are typically localized along lithological contacts or in fold hinge zones.
Also, extensive ancient workings have been identified within a series of carbonate rocks and
altered and weathered slates.
The Au-Zn (Ag-Cu-Pb) mineralization occurs usually in both carbonates and highly altered
volcaniclastics metasediments, while stratiform Zn-Ag (-Pb-Cu) mineralization occurs in
dolomitic-sideritic and carbonaceous pyritic shales. Ore grades are mainly confined to a distinct
stratigraphic horizon (Ore Horizon) within a basin-shaped structure (Small Syncline). The primary
sulphides consist essentially of massive banded pyrite, sphalerite, galena and minor tetrahedrite,
interbedded with laminae of pyritic carbonaceous shale, siltstone, chert, tuff and barite.
The red rocks in the upper levels/Roads/benches, and the outcrops in the background occur
in the leached capping. Bottom of the leached capping is usually composed of mixed oxide-sulfide
zone. Massive/brecciated smithsonite±hemimorphite occur within the iron oxide leached zone.
The oxidized/primary sulphide zinc minerals are associated with manganese oxides, iron oxides
and quartz veins. The gossans frequently contain large amounts of hemimorphite, which is a
typical weathering product of primary zinc sulphide mineralization. Major amounts of supergene
lead minerals and minor supergene copper are present in the gossans. Abundant visible gold
was observed in boulders of gossanous quartz from the mine workings, and also from an ancient
processing site located in a wadi immediately to the south-west of the southern ridge.
Rodruin's mineralization is interpreted as belonging to two fairly distinctive and different
styles: mineralization of background carbonate/gossan hosted "Hamama type" and mineralization
hosted in the shear zone. The surface mineralized zone extends from Aladdin's Hill to about 350-
400 m away and near to the high-grade underground Spiral Pit workings. At South Ridge-
Aladdin’s Hill, oxidation and leaching extend generally to 100 m below surface and, adjacent to
faults and other channel ways, to 300 m below surface. There is a highly variable pattern of
oxidation and leaching of the ore minerals but the Zn-Pb pyritic shales form the most resistant
feature of the stratigraphic sequence, outcropping as a lateritized plateau surface 60 m above the
surrounding plains. Five mineralized zones have been identified including: i) North Ridge (up to
32.10 g/t Au), ii) Central Valley Zone (CVZ; up to 7.08 g/t Au), iii) South Ridge (up to 9.59 g/t Au)
[Central Buttress Zone (CBZ; up to 9.05 g/t Au), and Spiral Pit Zone (SPZ; up to 35.30 g/t Au)],
iv) GF Zone (up to 18.60 g/t Au), and v) Aladdin’s Hill (up to 22.30 g/t Au).
In the present study, geology and geochemical investigations were carried out on weathered
profiles developed above Au-Zn-Ag (-Pb-Cu) VMS mineralization in Rodruin prospected area in
the Golden Triangle, Northern Portion of Eastern Desert-Egypt. Primary dispersion haloes of Cu,
Pb, Zn, Ag, and Au were studied around mineralized zones of the Rodruin Au-(Zn) gossan
deposit. Quantitative characterization using trace elements zoning of mineralization haloes based
on 279 weathered bedrock samples from surface is applied. This achieved based on a multivariate
statistical analysis (Factor analysis) of 5 selected trace elements.

2. Harraz, H.Z; Hamdy, M. M.; Aly, S.A. and Abd Ella, S.A. (2020). Geochemical Exploration and
Evolution of Rodruin Au-Zn(±Pb±Ag) Prospected Area in the Golden Triangle–Egypt. The
Eleventh International Symposium On Geophysics, Isg-11, Faculty of Science, Tanta
University, (Abstract).
Widespread mineralization has been identified at surface, and strong mineralization has
been confirmed at depth from the old workings. Rodurin's broad distribution of surface gold
mineralization has expanded the area over which mineralization has been identified. Extensive
gold mineralization is located at surface on the South Ridge of the Rodruin prospect, with
subordinate mineralization restricted to discrete high-grade zones on the North Ridge that is
structurally controlled. The results showed that Zn and Pb form relatively large primary haloes
that indicate their usefulness in arid intermountain regions in the Eastern Desert of Egypt as
guides for Au mineralization. The two metals, and to some extent Cu and Ag, have also high
mobilities in primary haloes. Distribution of Au anomalies indicate that the mineralization in the
area may be of two types. Pb and Ag distributions in unmineralized weathered bedrocks
accurately reflect bedrock Pb and Ag distribution and delineate lithologic and ore boundaries. Zn
distribution in weathered bedrock reflects the high mobility of this element under the prevailing
weathering conditions, with maximum concentration reached downslope from the Pb-Ag
anomalies. The Zn-Pb pyritic shales at Rodruin are conspicuously low in Cu and the Cu content
of weathered bedrock is of a similarly low order. However, at the nearby Aladdin Hill copper mine,
the distribution of Cu in weathered bedrock accurately reflects the structurally controlled Cu
mineralization.
The application of R-mode factor analysis estimated three statistical factors and factor score
maps are portrayed. Factor 3 (Au) significantly reflect the Au-mineralization (ore-controlled), and their
score maps enable a more precise delineation of auriferous quartz veins and the area which may
contain primary gold mineralization. Factors 1 (Zn, Cu, Ag) and 2 (Pb, Cu, (± Ag)) reveal the
distribution of Zn-and Pb-bearing minerals (supergene alteration factors).
Herein, we are discovering extensions and analogues of the mineralization of Aladdin's Hill,
as well as potentially important new mineralized gold-bearing zones around the Spiral Pit. A large
bulk minable gold project comprising wide zones of good mineralization exposed from surface,
with higher grade shoots contained within. The results of study indicated that, the geochemical
surveys using weathered bedrock samples are most effective, rapid and economical techniques
for detecting outcropping stratiform Zn-Pb-Ag and structurally controlled Au and Cu mineralization
in this deeply weathered environment of Gossan deposits in Golden Triangle at northern Portion
of Eastern Desert-Egypt.
Keywords: Exploration in Deep Weathering Profiles, Supergene, R-mode factor analysis; Multi-
element association geochemistry; Assessment of Au-Zn potentiality in Gossan;
Rodruin-Egypt