Marengus — Secrets of Chemical Pallas Revealed, ca. 1700

gold, or silver, or both. Gold or silver are very easily separated from the magnete magnet, here meaning the mercury that attracts them by the leather bag as was said above.

Imperfect metals that were extracted by the said water are recovered in this way. They place common water into the said water in such a quantity that the said water is weakened. Thus the imperfect metals are precipitated. They wash, dry, and melt the precipitated matter.

The said water for extracting imperfect metals must be made according to the following method. ℞ Take 10 lbs of common water, or urine, or vinegar. Add to it two pounds of Sulphuris scindi cleft or split sulfur and volatile sulfur, and 4 lbs of common salt. Let these be well dissolved in the said water. Sulfur does not touch gold, nor does salt affect silver. Thus, the said water dissolves and draws with it only the imperfect metals, leaving the gold and silver undissolved. Care must be taken, however, that the water is not too sharp or acidic, lest it dissolve the mercury. If it were to dissolve the mercury, it could not embrace the gold and silver or draw them to itself. Since it is the magnet, or mercury, that draws the gold or silver to itself, it must be added to the vessel over the mineral powders or before. Two pounds of the magnet, or mercury, should be sufficient for the above dose of powders to attract all the gold or silver that the mineral powders contain. The use of the said water will especially serve when the ores contain iron and other imperfect metals along with perfect metals.

Other methods

Some extract metals from ores as follows. They take mineral stones and heat them thoroughly among coals many times. Each time they are glowing hot, they cast them into common water and quench them. They repeat this until the impure and foul sulfur has left them. This will be known when they no longer emit a sulfurous stench. Afterward, they place the stones, broken in a coarse manner, into a furnace or a manicam long-necked furnace or sleeve. They place small pieces of lead underneath and melt them with a great fire, as has been advised. When the molten metal falls through the lower opening, it is fished out when cooled, washed, dried, and melted again. Finally, the perfect metal will be separated from the imperfect. That which comes out first in the above-mentioned fusion will be more perfect.

Other methods

It should also be known that many artists proceed as follows in extracting perfect metals. They take the washed and dried mineral powders as we said above, or they take metals or their Scorias scoria or dross in which gold is contained. They pulverize these well. Then, with the said powders and with fatty earth or clay, along with a due portion of common salt and a fourth part of salis nitri saltpeter relative to the weight of the common salt, they make a paste. From this they later form globes like the balls used in games. They dry these in a hot furnace using a wood fire. This drying can be done within an hour. They fish out the dried globes and dissolve them in an earthen vessel with boiling water, making a Lixivium lye. They pour this off, and in the said lye is contained the gold it has extracted. The gold is precipitated from the lye by adding enough common water to weaken it, so the gold falls to the bottom of the vessel. Then the precipitated gold is washed, dried, and reduced into a body with dissolved lead. From the said lye, the most perfect saltpeter can be made. By evaporating all the water over a fire, saltpeter will remain at the bottom of the vessel, and thus nothing will be lost.

It is to be noted that if the ore does not contain imperfect metals, but is only stripped of sulfur, it will be enough to wash the pounded and sieved mineral powders with some lye in which common salt is mixed, and afterward wash them again with common water.