with concentrated vinegar, placed in leaven and finally in ash.
Abu Bakr bin Muhammad Zakariya Razi writes:
Dahnaj (malachite) is Egyptian as well as Khurasani, but the Kir-
manian kind is the best. This, lapis lazuli, turquoise, and haematite
are the golden stones.
Probably he wrote this, as lapis lazuli has goossy eyes which are gold-like,
otherwise he knows all too well that lapis lazuli bears relationship to
copper, and, because of its coppery sheen, it looks more pleasing than
gold. About malachite and turquoise, he writes:
Both through the action of air become altered in their transparency
and opacity and some people, for this reason, do not like them."
The author of the Kitab al-Nukhah writes about malachite that it is
very green and has a tinge of rustiness. It has very slender black lines intersecting it and occasionally a mixture of redness is also found. Its one
variety is ta'usi (peacock-like) and the other is the muwashsha (printed).
The Kitab al-Mashahir says that dahnaj comprises green grains with
which gems are rubbed. Dahnaj is its noun singular. It would have been
nearer probability if it had been said by the author of the work that
gems and counters are made from it.
Sihar Bakht writes that dahnaj is hajar al-missan. He has elaborated
in support of this statement by stating that missan-i-'aqic] is the green
stone which is dahnaj. I fail to understand why he has said this, except
that both stones share their green colours.
This green colour looks pleasing in dahnaj and unpleasant in missan
Al-Kindi says he saw an old and broad malachite piece weighing nine
rath. The Sijzi variety of malachite is found in weights of up to 20
rath and the kind found in the deserts of Arabia weighs up to 10 rath.
The mineral which is taken out of Harra' Banu Salim weighs up to 2 rath
and the Kirmanian kind is one-half of one-sixth of a rati.
This stone is mined from the region of Khutan in the middle of a
valley of which the chief town is Ajmah. There is a valley by the name
of Fash from where the best white yashm is mined. No one can reach its
source. The large pieces of the stone go to the kings and the smaller ones
to the subjects.
There is another valley known as Qarafash. The yashm which comes
out of it is blackish and opaque and in some pieces the dark colour becomes so predominant as to assume an excessively black colour, as in
sabaj. A person who had visited this valley narrated that he had taken a
200 rati piece oi yashm for the king of Qatai in the old times.