tip for creating a soft black color using ASCP. Put Graphite ASCP over a coat of Aubusson Blue ASCP for a "very soft rich black". Put a coat of clear wax over that and end with a coat of dark wax. You will have a "deep, rich, but soft black".
Tips about applying dark wax over clear--drying times, re-activating, and doing dark wax after clear wax has dried. Annie Sloan Chalk Paint Wax Tips - this is an excellent post that has a lot of info on applying the products.