Musaeum metallicum

Etymology

of Lithar-
gyrium.

Lithargyrium litharge/lead monoxide can be referred to as lead dross, for it arises from lead that has been cooked for a long time in a furnace; for it is the foam that is collected while silver is purified, and it hardens like a stone. It is called lithargyros litharge from stone and silver, as it derives its name because lithos is stone and argyros is silver, as if it were a silvery stone. By the Arabs it is called Martech, and by the Latins it is called foam of silver. Dioscorides held that litharge could harden without silver while silver mixed with lead is purified in secondary furnaces. For at that time, with the mixture heating up, the lead, thinned by the violence of the fire and acquiring lightness, floats on top of the silver and becomes like dross, which the artisans, pushing it gradually to the sides, at last throw out, and he calls it gettha slag, which potters are wont to use afterwards. Some wrongly think that the foam of silver made from gold is called chrysitis, that from silver argyritis, and that from lead molybditis, when in fact litharge flows from lead alone mixed with other metals, and especially with silver, for the sake of easier fusion or purification. Although it sometimes acquires the color of gold and sometimes that of silver, that results from greater or lesser burning; for if it is taken from the crucible immediately as the burnt lead appears above the melted silver, then the litharge will shine with a silvery color; but if it remains there longer, it will acquire a golden color.

What

Gettha
is.

Differences

of lithar-
gyrium.

Artisans establish a double genus of litharge. They call one "natural," which comes out from a vein of silver mixed with a vein of lead and melted in furnaces; but the other is "artificial," which is prepared in the ways described above. Dioscorides shows three types of this: the first results from leaden sand perfectly cooked in furnaces, the second from the purification of silver, and the third from lead. Its species are called chrysitis gold-colored, argyritis silver-colored, and molybditis lead-colored. The best foam of silver is prepared in Meissen and Bohemia. Dioscorides, however, attributed the first rank to the Attic type, which, because it was made on Mount Laurium, was called Lauritis; he assigned the second to the Spanish type, and the third to the Puteolan type. For the sake of students, we figure the spontaneously formed litharge in this place under number 1.

A woodcut illustration depicting a textured mineral specimen, showing a layered and somewhat crystalline or rocky structure. On the right side of the illustration, the capital letters G and H are placed as reference markers.

Not unlike litharge is another filth of metals, which they name molybdæna molybdenite/lead-glance, or otherwise galena, because, according to the opinion of some, it is brought from Greece to Spain, although wrongly, if one is to believe Pliny, who denied that black lead is generated in Galicia. Nor is molybdæna, as Dioscorides wrote, produced from gold and silver; but this doctrine of Dioscorides is to be explained in this way, namely, while a vein of gold or silver is being smelted in furnaces, some lead is mixed with them, for since lead melts quickly, it accelerates the liquefaction of the gold or silver veins, and if lead were not added, those veins of gold and silver would be burned up rather than liquefied. Thus, from that lead mixed with veins of gold and silver, a certain excrement is segregated, which adheres to the walls of the furnace like icicles, and this is nothing other than molybdæna. Hence, it is more than manifest that the material of molybdæna is lead, whatever others may have written concerning two types of silver foam...
What

Molybdæ-
na is.