Considering that tin has a Pauling electronegativity of 1.96 and sulphur 2.58, and that a bond is considered to be ionic with a Pauling EN difference of approx. 1.7 at the least, would tin (II) sulfide be considered covalent?
This would be astonishing, since you would expect a metal—non-metal bond to be ionic. Indeed, many (non-academic) websites (such as this one) state that SnS is ionic. Evidence for the ionic character of tin (II) sulfide is the fact that it precipitates from solutions containing Sn(II) ions when adding hydrogen sulphide (which forms S(-II) ions) – thus, the two kinds of ions form a ionic compound (right?). Furthermore, SnS dissolves in hydrochloric acid, while typical covalently bonded networks such as silicon dioxide do not.
Finally, this paper states on the first page (which is freely accessible) that evidence for tin(II) salts with typical symmetrical ionic symmetries is completely lacking.
Thanks in advance, and happy holidays!