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Book I Minerals color, taste, odor , physical properties of gemstones and minerals such as emeralds, diamonds, rubies, sapphires

Book I Minerals color, taste, odor , physical properties of gemstones and minerals such as emeralds, diamonds, rubies, sapphires Page of 251 Book I Minerals color, taste, odor , physical properties of gemstones and minerals such as emeralds, diamonds, rubies, sapphires Text size:minus plus Restore normal size   Mail page  Print this page
BOOK I
17
gealed juices embrace sulphur, bitumen, realgar, and orpiment. Similarly, due to. insufficient knowledge and experience, he divides the genus of saline minerals into three species, namely, halite, alum, and atramentum su-torium. Halite has a saline taste but alum and atramentum sutorium have only a very faint saline taste. Yet the classes of meager congealed juices have been distinguished by taste and other qualities.
Albertus calls minerals which have the properties of both stones and metals by an intermediate name. He recognizes that metals character­istically melt in fire while stones do not. For this reason he considers stones to be dry and earthy, metals moist and aqueous. He regards intermediate minerals as having the properties of both a dry earth and a liquid. Certain of these are composed principally of earth, others of water. The inter­mediate minerals include halite, nitrum, alum, atramentum sutorium, or­piment, pyrite which is called marchasita by the Moors, pompholyx, and slag which is called σκωρία in the Greek language. By this classification minerals that have a mixed composition are called intermediate although actually pyrite is the only one that is truly intermediate since in this case stone is mixed and combined with a metal. Halite, nitrum, alum, and atra-mentum sutorium have neither a stone nor metal in their composition although they may be united and joined together with semi-stones. Arsenicum is rarely metallic, never intermediate. Pompholyx, concerning which Albertus has written, and slag are not natural substances but are produced in furnaces. Basing our classification on the above arguments, if we call intermediate only those minerals formed from water and earth, we will have in the intermediate class stones and metals which are composed of these elements. Since, however, some stones melt in fire and some do not, resistance to melting is not a characteristic of stones for if it is, then stones which melt would not be stones but intermediate minerals. No one has dared to say this, not even Albertus himself. Similarly Avicenna is not able to classify earths in any correct genus. Since I am about to discuss each genus of bodies formed in the earth, what it is and its nature, I shall regard earths as mixed minerals and, speaking frankly, disregard the opinions of certain of the Greeks.
There are two forms of subterranean bodies without life, one of which, because it is blown out and flows out from the earth we call by a charac­teristic name, the other we call mineral. A mineral body may form from portions of a similar substance, for example, gold, every particle of which is gold, or from dissimilar substances such as a clod which is composed of earth, stone, and metal. Actually it is separable into earth, stone, and metal. The former mineral body we call non-composite, the latter, com­posite. The non-composite bodies we divide still further into simple and mixed. There are four kinds of simple mineral bodies, earth, congealed juice, stone, and metal. There are many kinds of mixed mineral bodies which I shall discuss a little later.
Earth is a simple mineral body which can be worked in the hands when
Book I Minerals color, taste, odor , physical properties of gemstones and minerals such as emeralds, diamonds, rubies, sapphires Page of 251 Book I Minerals color, taste, odor , physical properties of gemstones and minerals such as emeralds, diamonds, rubies, sapphires
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