This is one of the passages I was referring to in another thread. It comes from the first epistle of the 16th century alchemist Antonio de Abbatia, which unfortunately was not translated into English (nor was it translated into German; the English translation was in fact made from the German translation of Abbatia’s second epistle), so readers of this language are not getting the entire picture of what this alchemist says. The following is my translation of the Latin passage where he more specifically contrasts the dissolution of silver in the secret solvent and that made with “common aqua fortises” (Thomas Norton in the 15th century had already used the solution of this same metal in “corrosive waters”, which he incorrectly thought was the method par excellence of the “multipliers”, as a specific example to point out that these liquors do not permanently alter and remain with the metals they dissolve, which can be recovered intact, both in nature and weight, from such solvents):

Concerning the operation of this water (i.e. the secret solvent of alchemy, which Abbatia has already been busy contrasting in more general terms with common aqua fortises in several previous passages)

If you want, dearest friend, to work with the above-mentioned water, to (he literally says “ab”, i.e. “on”) the white: dissolve most pure silver in the same, as much as you can dissolve, which once dissolved, separate it from the aqua fortis (he does not mean the common aqua fortises here, but the secret solvent of the alchemists, as he explained in the previous pages while contrasting both solvents, and he will again clarify next), and you will find our matter like an oil, and the weight increased by more than half; but such does not take place by means of the dissolution in the common aqua fortises, because in no way can the bodies dissolved in them congeal/coagulate, on account of the volatile spirits they contain; so there is no good or perfect solution, nor congealing/coagulating is possible from them.

For this reason, the wise worker should mix pure calcined silver in our aqua fortis, which is not common, but it is stronger than other waters, and is called, as we already mentioned, Great Lunaria…

Abbatia then continues describing some operations with the silver dissolved in the secret solvent, which end up giving a “fixed oil” or “fixed quintessence”.