On Stones – Theophrastus – English Translation



Of the substances formed in the ground, some are made of water and some of earth. The metals obtained by mining, such as silver, gold, and so on, come from water; from earth come stones, including the more precious kinds, and also the types of earth that arc unusual because of their color, smoothness, density, or any other quality. As the metals have been discussed in another place, let us now speak about the stones.

In general we must consider that all of them are formed from some pure and homogeneous matter as a result of a conflux or percolation, or because the matter has been separated in some other way, as has been explained above. For perhaps some are produced in one of these ways, and some in the other way, and others in a different manner. Hence they gain their smoothness, density, brightness, transparency, and other such qualities, and the more uniform and pure each of them is, die more do these qualities appear. In general, the qualities are produced according to the ac­curacy with which the stones are formed and solidified.

Some things are solidified through heat, others through cold. And probably there is nothing to prevent some kinds of stones being formed by either of these two methods, although it would seem that all the types of earth are produced by fire, since things become solid or melt as a result of opposite forces. There are more peculiarities in stones; for most of the differences in the types of earth concern color, tenacity, smoothness, density, and so on, but in other respects the differences are rare.

Stones, however, have these differences and in addition there are others that depend on their power of acting on other sub­stances, or of  being subject or not subject to such action. For some can be melted and others cannot, some can be burnt and others cannot, and there are other differences of this kind.

And some show a number of differences in the actual process of being set on fire and burnt, and some, like the smaragdos (1) can make the color of water the same as their own, whereas others can turn what is placed on them entirely into stone; some have the power of attraction and others can test gold and silver, such as the stone called the Heraclean and the one called the Lydian.

(1) A green stone, mentioned again in sees. 8, 23, 24, 25, 26, 27, 35. The usual Eng­lish translation is “emerald,” but this is not the exact meaning of the word. For the identification of this stone, see Commentary, sees. 23 and 24.

But the greatest and most wonderful power, if this is true, is that of stones which give birth to young. But the power of those used in manual work is better known and is found in more varieties. For some can be carved, or turned on a lathe, or sawn; there are some on which an iron tool cannot operate at all, and others on which it works badly and with difficulty.

And there are several other differences in addition to these. The differences that are due to color, hardness, softness, smoothness, and other such qualities, through which stones gain their special excellence, (2) are found in many varieties, and in some they occur in the whole of a district.

And among such stones there are the Parian, the Pentelic, the Chian, and the Theban, and these stone quarries have become widely known.  There is also the alabastrites, (3) found at Thebes in Egypt—this, too, can be worked in large blocks—and the stone resembling ivory which is called chernites; (4) and they say that Darius was buried in a sarcophagus of this material.

And there is the (variety of) poros, (5) which is like Parian marble in color and density, but has only the lightness of (ordinary) poros; for this reason the Egyptians use it as a frieze in their elaborate buildings. And a dark stone is also found in the same place, which is translucent like the Chian stone, and there are several other kinds in other places.

Such differences are common to many stones, as we have already said, but those that are due to the powers mentioned above are not found now in whole districts or in continuous or large masses of stone.

Some stones are quite rare and small, such as the smaragdos, the sardion (6), the anthrax, (7) and the sappheiros, (8) and almost all those

(2) See Commentary. s In all probability, onyx marble.
(3)  In all probability, onyx marble.
(4)  Apparently a variety of onyx marble.
(5) This could be travertine, but here it is probably a special kind of poros found in Egypt
(6) A red stone mentioned again in sec. 23 and described briefly in sec. 30. See Commentary, sec. 30, for its identification.
(7) Another red stone which is described in sees. 18 and 19. See Commentary, sees. 18 and 19.
(8) A blue stone which is described briefly in sees. 23 and 37. For its identification, see Commentary, sec. 37.

that can reasonably be cut and used as seals. (9) And some are discovered in other stones when these are cut up. There are a few which can be set on fire and burnt, and perhaps we should first explain the nature and extent of their differences.

Some of them melt and become fluid when subjected to fire, such as those which come from mines. For when silver, copper, and iron become fluid, so does their stony matrix, either because of the moisture in the matter it contains or because of the nature of such stones. In this way, too, fire-resisting stones and millstones become fluid along with the material placed on them by those who are burning it.

And some go so far as to say that all of them melt except marble and that this burns up and lime is formed from it. But it would seem that it is going too far to say this; for there are many which break and fly into pieces as if they are fighting against being burnt, like pottery, for example.

And this is natural since they have lost their moisture; for whatever can be melted must be moist and have a good deal of humidity. And  they say that some stones that are exposed to the sun become completely dry, so that they are useless unless they are soaked and wetted again, and others become softer and are more easily broken.

It is clear that both kinds are robbed of their moisture by the sun, but it happens that stones of solid texture become hard when they are dry, whereas those that are loose in texture, and those whose formation is of this kind, are easily broken and melted. Some of those that can be broken are like hot coals when they burn, and remain like this for some time, such as those found in the mine at Binai (10) which are brought down by the river; for when they are covered with charcoal they burn as long as air is blown onto them, then they die down and afterwards can be kindled again, so that they can be used for a long time, but their odor is very harsh and disagreeable.

There is a stone called spinos, (11) which was found in mines. If  this is cut up and the pieces are piled in a heap, it burns when exposed to the sun, and it does this all the more if it is moistened and sprinkled with water.

(9) The emendation ^irivres ray Kari) has been added to the text.
(10) The text uses the plural form (Binai), but the place was usually known as Bina.
(11) Probably some sort of asphaltic bitumen.

But the Liparean stone (12) is made porous when it is burnt, and becomes like pumice, so that both its color and density are altered; for before it has been burnt it is black, smooth, and compact. This stone is found in pumice, appearing separately in various places and not continuously, as if it were in a cell of a honeycomb. In the same way it is said that in Melos pumice is found in another kind of stone, and so the Liparean stone corresponds to this in the opposite way, as it were, except that this stone is not the same as the Liparean stone.

The stone which is found at Tetras in Sicily also becomes porous. This place is in the neighborhood of Lipara, and the stone is plentiful in the promontory called Erineas. Like the stone found at Binai, it releases a bituminous odor when it is burnt, and what remains after the burning is similar to burnt earth.

Among the substances that are dug up because they are useful, those known simply as coals are made of earth, and they are set on fire and burnt like charcoal. They are found in Liguria, where amber also occurs, and in Elis as one goes by the mountain road to Olympia; and they are actually used by workers in metals.

In the mines at Scapte Hyle a stone was once found which was like rotten wood in appearance. Whenever oil was poured on it, it burnt, but when the oil had been used up, the stone stopped burning, as if it were itself unaffected. These are roughly the differences in the stones that burn.

But there is another kind of stone which seems to be of an exactly opposite nature, since it cannot be burnt. It is called anthrax, and seals are cut from it; it is red in color, and when it is held towards the sun it has the color of a burning coal. One might say that it has great value; for a very small one costs forty pieces of gold. It is brought from Carthage and Massalia.  The stone found near Miletus does not burn; it is angular and there are hexagonal shapes on it. It is also called anthrax, and this is remarkable, for in a way the nature of adamas (13) is similar.

(12) Obsidian.
(13)  Probably corundum. See Commentary, sees. 19 and 44.

This power of resisting fire does not seem to be due to the absence of moisture, as is true of pumice and ashes. For these cannot be set on fire and burnt, because the moisture has been removed, and some think that pumice is formed entirely as a result of burning, with the exception of the kind that is produced from the foam of the sea. Their belief is due to observation and is based on what is produced in craters of volcanoes and also on the porous stone (14) which changes (15) to pumice when it is fired.

And the places where it is produced seem to prove this, for pumice is found especially in places that.. . , (16) But perhaps one kind is made in this way, and others in another way, and there are many methods of producing it; for the pumice found in Nisyros seems to consist of a kind of sand.

And it is regarded as proof of this that some of the stones which are found break into pieces in one’s hands and crumble into sand, as it were, because they have not yet become compact and solid. People find them in groups but in small amounts, (17) mostly about a handful in size or a little larger, whenever they scrape off the surface covering them.

And the sand is very light. The kind found in Melos is all . . . , (18) but some are produced in a stone of a different sort, as has been mentioned before. They differ from one another in color, density, and weight. They differ in color because the kind that comes from the lava stream in Sicily is black, and this stone and the malodes (19) differ in density and weight; for a pumice of this kind, having both weight and density, is also produced, and this is more valuable than the other in its practical use.

The one that comes from the lava stream can cut better than the white kind, which is light in weight, but the kind that comes from the sea itself cuts best of all. So much for pumice. But we must consider elsewhere the causes

(14) diabaros, perhaps diaboros.
(15) The Aldine text has oi (i.e., “which does not change”). Wimmer accepts this, but T) is found in the manuscripts (i.e., “which changes”).
(16) The emendation Kato/iciiois would mean “places that are burning”; irvpucaiarois would mean “places that have been subjected to burning.”
(17) Karh fiiKpa is used sometimes by Aristotle in this sense. Cf. Meteorologica, 370B, 5.
(18) The emendation <rx^Siv &s ev Hiaipif would mean “almost like the kind in  Nisyros,” but ev$pavaros, in \i$<? Si . . . would mean “easily broken, but is produced in a stone.”
(19) Malodes is unknown; melodes would suggest a pale-yellow stone, and mylodes would be a millstone.