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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
15
human eye; aegophthalmos, a goat's eye; lycophthalmos, the eye of a wolf; astroites, the stars; lapis eislebanus, pike, perch, various marine fish, and even a cock and salamander; pontica, mountains and valleys; agate and green marble, woods and streams. Under color of minerals I have discussed those that have lines of various colors but which do not resemble other things. Certain minerals are characterized by small spots similar to the stars in the heavens and for that reason are given the common name stellae. Lapis-lazuli, corallachates, and acopis have golden points, pontica, blood-red and black points. Lapis arabicus resembles bones just as other minerals resemble hair. Clear, white marl resembles the marrow of bones more than the outer portion.
Minerals vary greatly in quantity. Some occur in large masses as do marbles and rocks; others in small units, as certain stones and gems. Al­though Nature has given all genera of minerals a small and discrete body, nevertheless rocks, marbles, and earths often occur in great masses and it is necessary to separate portions from the parent body.
Thus minerals have differences which we observe by color, taste, odor, place of origin, natural strength and weakness, shape, form, and size. In order to make this knowledge clearer and more obvious, I shall explain which genera are outstanding and most important and which, in general, embrace all minerals.
Writers do not agree on how many and which these may be. Aristotle states that there are only two classes of bodies that form within the earth, namely, minerals, which he calls ορυκτά, and those substances from which metals are extracted and which he calls μεταλλευτώ. Others believe that there are three classes, stones, metals, and earths, which we cultivate. Avicenna mentions four classes, stones, stones that melt in fire and which are called πηκτός by the Greeks, sulphurous stones, and saline stones. Albertus places minerals in three classes, stones, metals, and an inter­mediate class. Aristotle is seen to classify subterranean substances in accord with the usage of the common people of Greece. I am of the opinion that he named well-known earths and even stones ορυκτά because they have only to be dug up and then they are ready for use and he called metallic materials μεταλλευτά because it is necessary to smelt them. Irre­spective of whether Aristotle bases his classification on common usage or not, he fails to recognize that metals are obtained from well-known earths and stones as well as from minerals. Since it is commonly recognized that this is true, the genus "mineral substance" embraces earth, stone, and metal. Even if we say, in order to please some critics, that these substances have been named μίταΧλΐυτά. because they are searched for and not because they produce metals, we are not able to defend and support his classifica­tion even with this interpretation. Since each is dug up the genus is "min­eral substance." These interpretations of his opinion have led us to the next theory. It has been said that we search for metals deep within the earth with little or no hope of finding them while stones and well-known
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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