For Otto Natzler, watching his wife Gertrud throwing a pot was a “sensual-aesthetic” experience. He noted “the graceful movement of her hands” as they exerted a continuous, progressively lighter touch until “that very last ‘breathing’ of her fingertips” produced a “sensitive flare of the lip to complete and balance the form.” In his notes, Natzler described the glaze on this bowl as “a very hard grey crusty lava glaze with bright turquoise overflow.” He went on to add, “The stark earthiness of the ‘Grey Lava’ is complemented by the heavy viscous overflow” to suggest earth and water, two of the physical substances that combine to make a pot. Natzler achieved the “Grey Lava” with silicon carbide, while the overflow blue is derived from copper.