I was kinda stalking your Sothyros tag (trying to find out more about this black stone thing; I need to re-read the books, evidently) and honestly, I think Sothyros might be incorporating many elements of the Americas too. (The element of mystery and exoticism at least, and southern Sothyros has diverse enough environments to sound like central and north America.) There are definite references to Africa (disease preventing major exploration, for example) but a lot to the Americas too.
Africa has amazingly diverse environments, and the element of mystery and exoticism is far stronger re “darkest Africa” than the Americas in the medieval literature and culture GRRM is referencing in ASOIAF. Basically because “the new world” hadn’t been discovered yet. And furthermore, the equivalent of the Americas is not on the Lands of Ice and Fire. (If they exist, they’re far west of Westeros, and no one has crossed the Sunset Sea to find out what’s on the other side.)
Also TWOIAF doesn’t describe southern Sothoryos? Only the north. No (white) traveler has gotten to the south and returned. The only long-distance explorer traveled for three years by dragon without reaching the end of the continent, and decided it was as large as Essos. It’s Africa. A mythologized, exaggerated, and unfortunately somewhat racist Africa, but let’s be real, it’s Africa.
P.S., you’re not going to find anything about the black stone in the books, as it was first mentioned in TWOIAF. Though we might get something in the future, since Sam will be in Oldtown where the Hightower is. edit: Let me correct that– Dragonstone was said to be made of fused black stone (Valyrian construction) and the Seastone Chair was described as made of oily black stone, but they weren’t called out as being something weird and strange until TWOIAF.
