I cleaned a small piece of limestone for a potential customer as a demo. It cleaned about like I would expect, nothing usual. It’s old limestone though, and in general the whole stone has a yellow hue. The customer wants it to be perfectly white like a fresh, straight cut piece of limestone he showed me.
Is there any way to actually whiten limestone? I know some people use OA to lessen the orange from iron in the stone, but I’d say this is a different scenario.