'THE GEOLOGY AND MINERAL RESOURCES OF DHUFAR PROVINCE, MUSCAT AND OMAN' [‎37v] (64/96)

magnesia), it can be seen how high is the quality of the material I
brought back from the Qarn Shaiba region, where material of this
quality occurs under many square miles of country within an easy
quarrying depth. If we reckon 2 million tons per foot thickness per
square mile, it is seen that a 10 -foot bed (which is really half the
exact thickness of the bed from which the second sample was taken)
holds 20 million tons per square mile. It is probable that some of the
‘ chalky ’ limestones in the coastal tracts, for example near Risut,
may also prove to be high grade dolomite. Unfortunately, I was
not aware of the exact nature of my two samples or I should have
taken samples near Risut, but I do not remember seeing such dead
white material or beds as thick as those near Hanun among the
exposures near Risut.
Edible Ceays
. 82. An unctuous clay, found in the shales of the Argillaceou:
series in the scarp of the Jabal Samhan facing Murbat, is used U
some of the people as an edible clay. I saw the excavations bu
did not know at the time the purpose for which the material wa<
utilized and believed it was for pottery-making and colour-wash
Mr. Little mentions as soapstone’ a clay associated with th<
iower beds of the middle Eocene limestone of Makalla (Gebel o]
Jabal Qara) which is used as a cleansing agent (detergent), and he
gives the following analysis for a sample of this ‘fullers earth
r S SlHca 53,60 %’ alumina 21-60%, iron oxide 1-60%
lime 2-40%, magnesia 1-87% and moisture, etc. 18-93% with s
specific gravity of about 2-13 (as found) and of a pale green coloui
(yellowish when dry). One of the best known edible earths (and
fuUers earth) m India is the ‘Multani matti’ of Bikaner, Jodhpur
etc which is also obtained m the middle Eocene of Rajputana. This
Indian clay is. of a slight greenish yellow colour (becoming biscuit
fPiWi ° n ^ ) ry 1 ln §), an ^. has t he following approximate composition
P a * ana ) : S 1 l lca 44-96%, alumina 14-16% iron oxide
4‘74 />, hme 8-72%, magnesia 4-63% and loss on ignition 20-72%
^reS^hr 6 ’ Und y r thellgniteof Kasai in Makalla, Little mentions
esseSk* 6 °/ 7P Ure soa P stone (with a composition
for seDk L in the i-f lr? . n a r d ma § nesium . which is correct
D°Ltir When W a PO wu SI1Cates) ’ ' which is moist and
Snctuouras th^ ef r e ^ OVed ' ,, When dry 11 is smooth but not so
if f J hat 1 of Q ara and sometimes feels slightly gritty.
like thr^fneT S °J 7 P laced m water, but does not swell up
like the specimen from G. Qara. The Qara fuller’s earth after
oSl volumf ^TheTk ^^ 17 ? ^ a , t ? r a - nd SweIls “P to twice its
a tlpicaL Wonite^ ^ an< ;l mat 1 erI , al 13 Slmilar . but still not quite
typical bentonite . When the Dhufar province is more thoroughly
searched
Jabal Sai
edible pu
As t
Carter’s
page 585
soft, whi
to the Nr
Then dis<
he wrote
strata of
dark-red
which th
there oc<
pass int(
thick, ni
appearai
more or
and ther
say, witl
it is of
Bedouin
called ‘ S'
sample,
83.
true flir
siliceous
Shaiba
(see pai
near Ri
of the '
of the J
of flint
grinding
made ir
yield sv
abunda
on the e
to colie
mounta
to find
(waters