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BOOK V. 



than this, because Nature bestows quantity in place of quaUty ; such ore 

 is mixed with all kinds of earth and stone compounds, except the various 

 kinds of rudis silver ; especially vdth. pyrites, cadmia metallica fossilis, galena, 

 stibium, and others. 



" that not only copper but also silver may be smelted from it, and indeed occasionally both 

 " copper and silver together. Sometimes, as is the case with pyrites, it is entirely devoid 

 " of metal. It is frequently found in copper mines, but more frequently still in silver mines. 

 " And there are likewise veins of cadmia itself. . . . There are several species of the 

 " cadmia fossilis just as there were of cadmia fornacum. For one kind has the form of grapes 

 " and another of broken tiles, a third seems to consist of layers. But the cadmia fossilis 

 " has much stronger properties than that which is produced in the furnaces. Indeed, it often 

 " possesses such highly corrosive power that it corrodes the hands and feet of the miners. 

 " It, therefore, differs from pyrites in colour and properties. For pyrites, if it does not 

 " contain vitriol, is generally either of a gold or silver colour, rarely of any other. Cadmia 

 " is either black or brown or grey, or else reddish like copper when melted in the furnace. 

 " . . . . For this cadmia is put in a suitable vessel, in the same way as quicksilver, so 

 " that the heat of the fire will cause it to sublimate, and from it is made a black or brown or 

 "grey body which the Alchemists call "sublimated cadmia" (cadmiam sublimaiam). This 

 " possesses corrosive properties of the highest degree. Cognate with cadmia and pyrites 

 " is a compound which the Noricians and Rhetians call zincum. This contains gold and 

 " silver, and is either red or white. It is likewise found in the Sudetian mountains, and is 

 " devoid of those metals. . . . With this cadmia is naturally related mineral spodos, 

 " known to the Moor Serapion, but unknown to the Greeks ; and also pompholyx — for both 

 " are produced by fire where the miners, breaking the hard rocks in drifts, tunnels, and 

 " shafts, burn the cadmia or pyrites or galena or other similar minerals. From cadmia is 

 " made black, brown, and grey spodos ; from pyrites, white pompholyx and spodos ; from 

 " galena is made yellow or grey spodos. But pompholyx produced from copper stone (lapide 

 " aeroso) after some time becomes green. The black spodos, similar to soot, is found at 

 " Altenberg in Meissen. The white pompholyx, like wool which floats in the air in summer, 

 " is found in Hildesheim in the seams in the rocks of almost all quarries except in the sand- 

 " stone. But the grey and the brown and the yellow pompholyx are found in those silver 

 " mines where the miners break up the rocks by fire. All consist of very fine particles which 

 " are very light, but the lightest of all is white pompholyx." 

 Quartz Minerals. 



