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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
9
completely saturated with water. All earths can be saturated with water and certain congealed juices.
Minerals differ even more in other qualities which are perceived by touch and which reveal the position of some, and in the well-known quali­ties due to strength and weakness, namely, unctuousness and meagerness, density and porosity, hardness and softness, roughness and smoothness, heaviness and lightness, and many others.
Some minerals are unctuous such as marl, sulphur and jet, while others, such as ocher, salt, sandstone, and almost all stones, are meager. There are many more meager minerals than unctuous but among the latter there are some which are completely unctuous such as sulphur, bitumen, amber, jet, etc., and some which are semi-unctuous such as spinus and many others which I shall classify as "mixed." Although most minerals are dense, some are porous, for example, pumice, travertine, and the chalk used by painters. The parts have not been joined and connected, one with the other, on all sides and they contain much air. Many minerals are hard but stones and metals are especially so. Spodos, lime, and earths which have been moistened with water are soft. Emery, Melia earth, and the earth they call "tripela" (tripolite) are rough for these have sharp points. Most gems, refined metals, and even native metals, the parts of which are uni­form, are smooth. Generally all minerals are heavy although jet, mineral ebenum, pumice, and travertine are light. Some minerals have openings too small to be seen by the eye and in these is a quantity of air which mixed with earth and water is contained in the entire body of the mineral. A mineral which is full of openings that can be seen by the eye is called polemikos in Greek and fistulosa in Latin.
Minerals differ in the degree of the qualities mentioned above, for ex­ample, amber is more unctuous than jet, sandstone is more meager than ocher, and another is intermediate between unctuous and meager. The concept of degree in qualities was understood by the older writers on agri­cultural subjects for they say that one earth is rich, another poor, another intermediate.
Now I shall consider how minerals differ in other well known qualities due to strength or weakness, namely how they resist destruction. Certain minerals dissolve in moisture, such as earths, halite, nitrum, alum, atra-mentum sutorium, etc.; others in fire, such as the stones the Greeks call τηκτόs and our miners, if I may be allowed to translate the German word, call fluores.1 Many of these are very similar to gems. Transparent gems themselves melt in fire as well as silex, stones which produce the sands from which glass is made, metals, and especially many mixed minerals. Some of these melt quickly, some slowly. Earth which if soft, porous, and meager dissolves quickly in liquid while earth which is hard, dense,
1 Fluorite, Germ., flusse. The Latin name from which fluorite is derived is the verbal noun fiuor.
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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