So I need to make gray fondant for a cake next weekend and all I have access to are wilton colors. I tried using a small amount of black but it gets a weird purple-y color, any suggestions? TIA

i use coal balck. seams to work alright

I have always just used a bit of black and haven't had any problems with it looking purpleish.

Your black icing color may be old. Wilton tends to turn purply/pinky as it ages. Even if you just bought it, who knows how long it was sitting on the shelf.

Another thing you might try... knead a generous amount of black into a small blob of fondant. Let it sit overnight. Next day, knead just a tiny bit of the black fondant into your white fondant. (Test a small piece first, in case you get that purply problem again.) Add tiny bits until you get the shade of grey you want.

thanks so much, I will try that.