No. When you separate gold from silver by means of nitric acid the calx is black or dark. When you seprate it from copper, though, the calx is reddish-brown, it looks a lot like precipitated copper. But that happens even at the first separation. No amount of further separations from copper seem to deepen this color of the gold calx. At least I could not notice it.
As I understand it, the whole thing hasn't anything to do with the colour of the calx which is produced after the parting. The redness must be discerned at the metal which we get after the melting of that calx. Till far I have accomplished four melting and partings and the metal which I get after the melting of the produced calx has the usual colour of gold, not a red one. Do you make use of propane - oxygen torch for your meltings? Our conclusions seem to agree then.
No, I just granulated the alloy by pouring it in a metal bucket full of agitated water. Division to calx is not necessary for nitric acid to act upon such alloys that contain much larger quantities of copper or silver than gold. Even in a solid nugget or ingot the acid will work its way through the alloy, eventually.
Yeah, granulation sounds good too. From my part I use a solid nugget of the alloy but the reaction takes a lot of time to reach the end. I have heard that its dangerous to pour molten copper in water. That the reaction is violent. Have you found anything like that?