No, "Pure Black" in Silkies is not genetically different from B/B/S breedings. None of them appear based on Extended Black - they are mixed bases with lots of melanizers to make them black. Charcoal is probably one of them - for the nice black head. There are a lot more - both for the feathers and for the skin. But if you breed Black to Black and do not mix in the blue you may get doubled copies of the melanizers for a blacker black - and its possible to get very nice Black birds if you can get a doubled E^R base instead of the mixed bases. In other words - remove any chicks that look like chipmunks or are lighter on the bottom from your breeding program. Use only extremely black chicks. No lighter toes - no lighter feathers - that chick has all the melanizers to make a very dark solid black. However - now that I have been seeing Silkie chicks that ARE based on E - perhaps that is the way to get really black blacks.
I like the Partridge color in other birds, its what drew me to investigate Partridge Silkies - but I do like the Silkie version to be slightly lighter than the dark ones. On Silkied feathers the differences between the dark red and the black don't show up quite as well. Still, I prefer the richer colored Partridge girls that are colored all over to the black with gold overlay patterned birds or the washed out Buff versions. Personal preferences, as you said. I am not enamored of my PWB boy's colors for the Silkies - it would look almost all black on Silkies. But if that gives me correctly colored girls..
I don't know where the Mahogany came from that Sonoran found .. and I haven't seen a genetically Red Silkie in a long time. Red carries Mahogany,. But once again we have Silkie birds with mixed genetics being named a color because that's what they sort of look like. I have some Buffs that have autosomnal red now ( I crossed Buff and Partridge) - very nice and dark overlay over the Buff. Somebody said it looked like a Red - no - it isn't. I don't think he carries Mahogany, so I doubt the "Red" birds with autosomnal red would work. I asked Sonoran on another thread if a Partridge boy I have here could carry Mahogany, I am hoping for a positive reply![]()
Please get it tested. We can't diagnose over the internet. You need to know exactly what you are dealing with.
There's nobody around me to do it other than the guy that probably gave it to her.