Was Heathcliff black?Some suggest he may have been black, Arab, or mixed race. What in the text would suggest this?

The text describes him as dark and swarthy; when Mr.
Earnshaw brings him home in chapter 4 he calls him "as dark as if he belonged to the
devil," and his wife describes him as a "gypsy brat." We are told that he has black hair
and eyes, and it seems implied that he might have a gypsy background, which would give
him an alien and non-european racial origin. It would not be inconsistent with the novel
to suppose that he had African ancestry as well. However, Heathcliff is a fictional
character, so we cannot find out any more about him than the author tells us, and the
author says nothing which would imply that he was partly black or had an African origin,
in particular, rather than being merely dark and swarthy. In chapter 3 the adult
Heathcliff is described as "white as the wall behind him" from fright. If he could
blanche white from fear it is probable that he had a comparitively light complexion, and
was only considered dark in comparison to most English.