BOOK VI	147
	Draconites or dracontias is said to come from the brain of a dragon. Saurites is reported to come from the stomach of a green lizard that is caught in traps. Even though the former may be artificial and the latter could be found I have never seen either one offered to us. Since I have said that margaritas (pearls) command a high price it occurs to me that I should say something regarding the relative value of the precious gems. Diamond is the most valuable gem and is followed in turn by the Indian pearl, emerald, opal, ruby, jasper, lapis-lazuli, sapphire, asterios and chrysolite. Next comes chrysolithus, amethyst, hyacinthus, prase, agate, belt oculus and finally the other gems. However, a poor diamond will com­mand a lower price than a fine ruby (carbunculus), a large chrysolite will sell for more than a small emerald and an agate that contains an excep­tional image is more highly prized than an inferior opal. The inhabitants of the region in which a certain gem is found regard it as of little value since it is so common and yet these same people regard the gems that oc­cur in other regions as having a great value since, to them, they are rare and unusual. As a rule, great and noble men attach great importance to the gems they possess. Gems are not only set in rings, brooches, neck­laces and bracelets but they also embellish the crowns of nobility and even the statues of them, for example, the copper statue of Caesar of Saxony at Goslar. They may adorn the statues of saints as that of Saint Valerius of Goslar, They are set in the statues of famous men, for example, the one of Pega \'ipertus of Misena. Anyone who wishes to study gems should examine these statues and the royal crowns whenever the opportunity arises. In the magnificent temple of St. Mark in Venice the tablet of the high altar is set with precious gems and since the temple is open daily one can examine it as well as the crown of Cyprus and other gems that are placed on display.