soapstone works well, but I found a chalk at Jo-anns that doesn't come off when FMQ, I need to go back and purchace, one of my quilt buddies bought one and I've used it--works great, even tried rubbing it off with my finger and it did not come off. Yellow package w/7 white calk sticks and a veriety of other colors for 14.99 refills were 7.99.