are used in the making of vessels and utensils, goblets and cups, chess
pieces and counters, and pieces as large as the soap-nut. But this variety
does not approach the Zanji kind nor is the quality of the workmanship
of these people (i.e., of Kashmir) as finished as that of the Basrans. Its
sections are found in mountains as well. It is found in plenty in Wakhan
and Badakhshan but is not exported.
Al-Kindi writes:
The best crystal is the A'rabi which is picked from the desert among
the gravel. It is found encapsulated in a thin turbid sheath and
weighs up to two rath. It is similarly picked from Serandib, but it is
less transparent than the A'rabi.
Some crystals are excavated from the earth, and the one mined from
Arabia is good. Al-Kindi says he had seen a piece that weighed more
than 200 rath but it was cloudy for the most part and had perforations.
There is a crystal mine in the frontiers of Armenia and Badlis, and the
colour of the crystal mined from there is pale.
Nasr has classified the crystal into four kinds. He has mentioned all
the characteristics of the A'rabi kinds enumerated by Al-Kindi. But he
has added the observation that when sunlight impinges upon it, it presents the colours of the rainbow. 101 Nasr ought to have said that such
crystals are broken, as the pieces that are intact do not reflect the
colours of the rainbow. The reason is that it is like pieces of ice and such
colours are visible in the pieces too. The second kind is the gliaymi. so
called by way of similitude, as ghaym means the cloud. The third kind —
the Serancfibi — is nearest to A'rabi in the attributes but not in transparency. The fourth kind which is mined is better than the A'rabi. Nasr
gives another kind which has caught the odour of smoke and fire. This
kind is the most inferior.
In the Lapidary it has been stated:
Crystal is a kind of glass which is found in glass mines in the form of
a congealed body. If glass is found in a dispersed state, it is collected
by means of magnesia.
Some authors, following upon the heels of Nasr, have written in their
books that the crystal is a glass-like mineral, whereas glass is an artificial
variety of crystal.
Hamzah says that crystal in some ways resembles glass but is not
made from it. This is possibly so because both are transparent and whatever is inside them is visible. But as regards melting they are distinctly
different as, while glass melts, crystal does not, as we shall discuss later.
But I have neither observed this nor tested it.
Some authors have said that crystal is congealed water. This is what
I also say as I shall elaborate later. Since it is like limpid water, it has
been compared to hydrated stone and water bubbles. Ibn al-Mu'tazz
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