A OPEN PIT MINING AÇIK OCAK MADENCİLİĞİ

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two main pudding layers met the wadi with a
down-slop dip, because this setting fostered
a “controlled” slip-down of the extracted
stone-blocks.
In one of the quarry, probably worked out
by the Romans, an undercut technique was
used which led to a general rock-fall of a
huge mass of the pudding layer down into
the wadi bottom.
The fallen blocks were up to many cubic
meters in volume and therefore were later
cut into smaller blocks dressed to the right
size. In order to reduce blocks to the right
size a line of wedge-shaped holes was
chiselled, and then subsequently iron wedges
were inserted into the holes and hammered
until the block split along the line of holes
(Fig.6).
Figure 6. The main quarry of “Breccia Verde
Antica”: the outcrop was dismantled
according to its natural discontinuity
network, the fallen blocks were subsequently
dressed to the right size.
Wedging was used for rough splitting,
but, for a more controlled cut, quarriers used
the “pointillé” pits method: a straight line of
small, shallow pits was chiselled across the
block surface, then quarriers inserted special
short chisels along the pits and hammered
them back and forth until the block split
away (Harrell & Storemyr, 2009).
4.2.3 - Use
In the Pharaonic period the Breccia Verde
Antica was seldom used: the fragment of the
head from the lid of the inner sarcophagus
belonging to Ramses II is considered to be
made of “green conglomerate”, and the
sarcophagus of Nectanebo II as well (both in
the British Museum) (Aston et al., 2000; De
Putter & Karlshausen, 1992). “Breccia Verde
Antica” was used by the Romans to make
many beautiful bowls and other objects, the
most outstanding ones being the column,
made by the order of Emperor Justinian (VI
Century A.D.) for the church of San Vitale
in Ravenna (Italy), where it still is, and three
other columns in Rome (Borghini, 1989;
Harrel et al., 2002).
4.3 Granite of the Wadi Umm Fawakhir
Close to Bir Umm Fawakhir there are some
small granite quarries.
4.3.1 - Geology
The granite is actually a mainly a pinkishgrey,
coarse- to mainly medium-grained
granodiorite referable to the older granitic
complexes. The granite is massive, affected
by two sets of sub-vertical fractures N-S and
E-W trending, respectively. These fractures
can be grouped into bands with fractures up
to a meter wide or can be scattered and
spaced some meters wide; flat lying joints
(Closs, 1922) are also present. The granite
surface is fresh to slightly weathered mostly
along the fractures (Thuro & Sholz, 2003);
all the fine particles had been removed by
wind and rainfall; large amounts of residual
core stones are present.
4.3.2 - Quarrying
The quarriers used boulders and cobbles or,
due to it massive setting (Fig.7).
Figure 7. The main of the small granite
quarries at Bir Umm Fawakhir.
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