Book VIII metals, precious such as gold, platinum, silver Page 194



	182	DE NATURA FOSSILIUM

	I shall now take up iron (ferrum). None of the older writers mentions it as being found native. However, on rare occasions, it is mined or found in river sands with its characteristic color. It is not entirely pure as compared with the black pebbles from which tin is obtained since the latter are purer and require less smelting than small masses or fragments of iron. Albertus knew of this for he writes, "Iron is found in watery earth similar to millet seeds and having a large amount of dross."²⁵ Rough iron is black, polished iron grayish white. When smelted from its ore it liquefies and can be cast. After it has cooled and the slag has been removed it is heated in a fire and softened so it can be hammered into sheets although it cannot be cast. Yet if it is again placed in the proper furnaces it can then be cast. All iron is hard and because of this produces the clearest tone of all metals. One iron will differ greatly from another. The best is tough, intermediate varieties are moderately tough while inferior varieties are brittle and full of air. The iron from Sweden, Norway, and Noricum is the best. Iron of intermediate quality comes from Lauenstein and Gishubelan, Misena, and Sulcenbach in the mountains of Noricum beyond the Danube. The iron the Greeks call στόμωμα and the Romans acies, if I am not mis- ²⁵ Agricola refers to iron in other writings. In De Ortu et Causis Subterraneorum, page 79, "I shall now consider the strength of metals. They all melt because they contain water. Iron contains an exceptional amount and for that reason is more ductile as is indicated by the name of Swedish iron, osemulum. Unrefined iron is not so ductile because it contains so much earth and because there has not been a good mixing of the earth and water. However it is soft because the humor no matter how small the quantity, set free by the fire commences to be dissipated." Page 77, "A mass of iron weighing fifty pounds fell near Lurgea and because of its hardness could not be broken. A portion of this mass has been sent to the King of Torat. He ordered that swords should be beaten out of it but it could neither be broken nor beaten out. The Arabs say that the German swords, that are the very finest, are made from this kind of iron. Avicenna writes that the Arabs allowed this deception by the merchants themselves. The iron used by the Germans does not fall from the sky but is dug from the earth. But yet Avicenna tells us that both iron and copper fall like rain. He relates that in the Roman annals, mention is made of rains of earth and of stones and we have seen it rain yellow earth several times in the fall. It is not extraordinary for all of this material to be created in the air from time to time for in no other place do we find a more sudden mutation of the elements nor more violent reactions." De Veteribus et Novis Metallis, page 391, "Certain metals take their names from countries. . . . Iron, especially the variety στόμωμα (steel), is called chalybs by many because the Chalybes made the first iron." Page 412, "Iron mines are found almost everywhere. Strabo writes that the ore is found on the hills of Britain and Pliny mentions it from northern Spain and all parts of the Pyrenees as well as on the Cantabrian coast where, he says, some of the incredibly high steep mountains are composed entirely of iron."