A OPEN PIT MINING AÇIK OCAK MADENCİLİĞİ

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petrographic assemblages are the same,
though the geological origin is totally
different.
Therefore for this ornamental stone the
name Basanite has been dismissed and now
the original name is used, bekhen-stone.
During our field work we surveyed several
quarries that exploited the bekhen-stone.
4.1.1 Geology
In the Wadi Hammamat, the bekhen-stone
outcrops for about 2km, corresponding to the
Um Hassa Greywacke Member of the
Hammamat Group and consisting of (Aston
et al. 2000) dark greenish-grey to mainly
greyish-green, medium- to very finegrained,
occasionally pebbly, chloritic
greywacke, mainly composed of fine to very
fine sand grains (0.06-0.2mm) and darkgrey-green,
basalt-looking, siltstone. This
last lithofacies outcrops mainly in the
eastern side of the quarry area.
The grains are mostly quartz, with minor
oligoclase-andesine plagioclase and felsic to
intermediate volcanic rock fragments plus
rare muscovite. The matrix is composed by
chlorite and sericite plus minor amounts of
epidote and calcite. The layering dips 45°
towards the east.
The bekhen-stone rock-mass presents
three joint sets: two vertical, at about 90°
and trending around E-W and N-S
respectively, and one sub-horizontal; the
joints are up to a few meters spaced so they
delimit natural blocks up to a few cubic
meters in volume.
4.1.2 - Quarrying
The slopes of the wadi are generally covered
by debris, therefore we can suppose,
according to the general geomining
concepts, that the first quarries were opened
in the lower outcrops at the base of the
slopes. When the highness of the quarry face
made further exploitation of the quarry
difficult, in combination with the difficulty
posed by overhanging debris, quarriers
moved the quarrying activity to an upper
outcrop, creating access with tracks and
ramps and sledge-ways for handling blocks
and setting up new logistics.
Most recently Spencer (2011) reports the
finding of “four hitherto unknown Early
Dynastic quarries located at high elevations
on the Bekhen Mountain”.
Quarries were opened in the main natural
outcrops, on the cliffs bounding the wadi.
Quarriers used the three sets of joints (Fig.4)
as preferential surfaces to dismantle the
rock-mass into blocks and then let them fall
down the slope to the wadi floor.
Figure 4. The main outcrop of the bekhenstone:
the three almost orthogonal joint sets
which were used in order to dismantle the
rock and collect cut blocks down-slope.
One of the main problems was to
dismantle, but keep intact while being
transported down-slope, a block of stone the
right size for the ordered statue or
sarcophagus. According to an inscription,
Meri, the leader of a quarrying expedition in
the reign of Amenemhet III (ca.1,810 B.C.),
in order to keep the stone blocks intact
down-slope, built the first inclined plane
(sledge-way) to slide the blocks down
(Montet, 1959). The Romans built a very
long sledge-way in order to bring down
blocks from a quarry opened up in the slope
(Fig.5).
In order to dismantle the rock-mass and
dress the blocks, quarriers used handspikes
of stone and later copper, bronze and iron
tools and chisels, and wood hammers
(Harrell & Storemyr, 2009).
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