gems, pearls, Arabic mineralogy, al-Biruni, famous pearls, al-Yatima pearl, Arabic Mineralogy, Islamic jewelry, Islamic gems

Exquisite pieces of jewelry with huge precious stones were, and still are, objects of irresistible attraction to everyone. Their beauty and rarity captivate, and above all their adventurous, if occasionally legendary, histories and royal genealogies are fascinating. Among the world-famous gemstones whose history is said to go back to the medieval period is the Timur ruby in the collection of Her Majesty Queen Elizabeth II, which bears the names of several other royal owners in addition to the great Timurid ruler Tamerlane (1336–1404). Another is the so-called Hope diamond, now in the Smithsonian Institution, Washington, D.C., which was probably bought in India by the French merchant Tavernier, who later sold it to King Louis XIV. It was kept until the French Revolution in the royal collection, reappeared in 1830 in London, and was bought by the banker Henry Hope after whom it is named. It was presented to the Smithsonian by the New York jeweler Harry Winston. Of no less fame is the so-called Smaragd Karls des Grossen (Charlemagne’s emerald) in the treasury of Mittelzell-Reichenau which, though made out of a large piece of emerald glass (length: 56 cm, height: 37 cm, and width: 3 cm), was regarded until the eighteenth century as the biggest emerald in the world and was traditionally said to have been given to Charlemagne by Harun al-Rashid. It should be pointed out, however, that a certain huge emerald (smaragdum magnum) was mentioned in the Chronicon Mundi (completed in 1236) of D. Lucas, the bishop of Tuy. He says that the splendid stone was given by King Alfonso VII to King Louis VII on a visit that the latter paid to the church of Santiago de Compostela, probably in 1154. He adds that the stone was presented to Alfonso VII by King “Zafadola”—that is, King Sayf al-Dawla, ruler of Rueda de Jalón in Aragon—and that it was carried by King Louis back to France; Louis later presented it to the monastery of the Blessed Dionysius.