This is what Fulcanelli mentions on the production of nascent gold from silver via dissolution in nitric acid:

"Pour into a tall tubular glass retort a third of its capacity of pure nitric acid. Attach to it a receiver with an exhaust tube and set the apparatus on a sand bath. Operate under a fume hood. Heat the apparatus gently without reaching the boiling point of the acid. Then stop the heat, open the neck and introduce a thin fraction of virgin or cupeled silver that contains no traces of gold. When the emission of nitric peroxide ceases and the effervescence has calmed down, allow a second portion of pure silver to fall into the liquor. Thus repeat the introduction of the metal, without haste, until the boiling and emission of red fumes manifest only little energy, signs of approaching saturation. Add nothing more, Let it settle for a half hour, then cautiously decant your clear, still-warm solution into a beaker. You will find at the bottom of the retort a thin deposit in the form of fine black sand. Wash it with lukewarm distilled water and let it drop into a small porcelain capsule. You will find out through testing that this precipitate is insoluble in hydrochloric acid, as it is in nitric acid. Aqua regia dissolves it and yields a magnificent yellow solution, absolutely similar to that of gold trichloride. Dilute this liquor with distilled water; precipitate it with a sliver of zinc; an amorphous powder, very fine, dull, of reddish-brown coloration will be deposited, identical with that given by natural gold reduced in the same manner. Properly wash, and then dry this powdery precipitate. By pressing it on a sheet of glass or marble, you will get a brilliant, coherent lamina, of a beautiful yellow shine in reflection, of a green color in transparency, having the appearance and the superficial characteristics of the purest gold.

In order to augment your minute deposit with a new quantity, you can do this operation as many times as you wish. In this case, take again the clear silver nitrate solution, diluted by the waters of the first washing; reduce the metal with zinc or copper; decant and abundantly wash when the reduction is complete. Dry this powdery silver and use it for your second dissolution. By continuing in this manner, you will amass enough metal to render the analysis much easier. Furthermore, you will be assured of its true production --- even if the silver that you originally used had some traces of gold.

But this simple body, so easily obtained, although in a very small proportion, is it truly gold? Our sincerity compels us to say no or, at least, not yet. For even if it shows the most perfect outer analogy to gold, and even most of its properties and chemical reactions, still one essential physical characteristics is missing: density. This gold is less heavy than natural gold, although its own density is already greater than that of silver. We can therefore regard it as, not the representative of a more or less unstable allotropic state of silver, but rather as a young, or nascent gold, which further reveals its recent formation. Moreover, the newly produced metal remains capable of taking and keeping, by contraction, the increased density that the adult metal possesses. Archemists used a process which ensured nascent gold al the specific qualities of adult gold; they called this technique maturation or firming up, and we know that mercury was its principle agent. We find it mentioned in some ancient Latin manuscripts under the expression of Confirmation."