Ancient Jasper is a fluid, opaque glaze that transitions from soft black to olive green to rust red as it is applied thicker. This glaze has an active, varied surface by itself and layers with our other Potter's Choice glazes with striking results. Ancient Jasper benefits from a heavier application. This glaze will produce reds on all clay bodies, although iron-bearing clay bodies will produce the widest range of colors. No special cooling cycles or soaks are needed. Soaking can actually diminish the reds.