Ironed over Pounce
 

I ironed over regular pounce. Does it set it? Will it come out with washing?

Take a wet washcloth and test to see if it washes off. If a washcloth removes a bit of it the rest will probably wash away when the quilt is laundered. I usually use a damp cloth to remove pounce chalk

It is fine chalk powder so will wash out. Pounce makes an iron away powder too.