THE TURQUOISE.                             265
	blue, inclining slightly to green. In many specimens the green becomes more. pronounced with age. This mineral has never been found crystallised, but occurs as veins, nodules, stalactite masses, and incrustations. It takes a fair polish, and exhibits a feeble lustre. The Lapidary usually cuts it en cabochon, or with a low convex surface. In the East it is frequently engraved with Persian, and Arabic inscriptions, generally copied from the Koran ; the incised characters being in many cases gilt. Such objects are worn as amulets. The Turquoise has always been associated with curious superstitions; the most common being the notion (already alluded to) that it changes its colour with variations in the state of its owner's health ; or even in sympathy with the affections, and the characteristic physical influences of its wearer. That personal health determines the brilliancy, and beauty of jewels worn next the person of sensitively gifted persons, is a recog­nised fact. Mediaeval writers were fully aware of this phenomenon. Thus, concerning the Turquoise, De Boot (1636) has related how it grew paler as its owner sickened, lost its colour entirely at his death, but recovered it when placed upon the finger of a new, and healthy possessor. Again, " Whoever," says Van Helmont (1620), " wears a Turquoise, so that it, or its gold-setting touches the skin, may fall from any height; and the stone attracts to itself the whole force of the blow, so that it cracks, and the person is safe." This particular virtue, however, at the present prosaic matter-of-fact time we altogether dispute, and should decline to put it to the test. Van Helmont, who was highly intelligent, believed in the Archaus, the soul of man after Eden, as the first cause of all diseases.