and discoveries, in two separate maqalas or treatises.
The First Maqalah on Gemstones
The first part of the book is devoted to gemstones, their properties,
types, colours, origin and monetary and aesthetic values, in the following order.
Corundums
Foremost are the corundums, rubies, sapphires and emeralds known
and mined since remote times. Up to the present, they were largely
sought after and highly priced and valued. Among the corundums, the
commonest were the opaque white, the yellowish, reddish and purplish
carmine types. The green varieties are known in considerable quantities
in the mineral species of beryl existing in several colours. The rubies
and spinels follow. Nonetheless, the special value of corundums lie in
their very rare green colours, chemically known as beryllium aluminium
silicate (Be3 Al12 Si6 018). Many Muslim caliphs and sultans amassed
precious and priceless jewellery in their treasuries. However, as indication of the rulers' appreciation and admiration, Beruni refers to a very
rare spoon made of genuine green corundum of great value. It was sent
as a gift to the 'Abbasid Caliph al-Mutawakkil (232-247/847-861) by
his court physician. Another priceless, large corundum was received by
the Ghaznawid Sultan Mas'ud (about the 1030s) while residing in the
city of Rayy. It was admired by Beruni for being unusually exquisite.
The King of Gemstones
The gemstone that is considered the jeweller's best friend, and is
regarded as the backbone of his trade as well, is the diamond. In
modern jargon, it is composed of almost pure carbon. The naturally
occurring varieties have a specific gravity of 3.5 involving weight and
size, and measures in the generally accepted guide regarding the so
called Mohs' scale of hardness as 10- as relatives to resistance to
scratching and general wear. Therefore, among all gems, it is the most
brilliant and durable.
Diamond varieties range in colour from the colourless to the waterclear, or are tinted with red, blue, yellow, brown and other hues. The
igneous origins occur in many deposits of rock layers. And in view of
their rarity, intrinsic and aesthetic values, beauty and durability they
remain forever intriguing and considered legendary and superlative.
Since remote antiquity, men discovered and assigned special worth
to rare jewels. For their sake, assassinations and infamous robberies
have been committed, wars fought and dynasties fell while others arose.
However, within the trade, diamonds, corundums, sapphires, rubies and
