Sun Chao's zinc crystal flower form is even more beautiful than the yao pien and oil spot of former times. In terms of technology, the formation of zinc crystal is more difficult to achieve than ferric crystal. The reason for this is that it must be heated to a temperature of 1,300 ℃.
和古人相比，孫超的鋅結晶為花朵狀，由於晶體面積大，本身又會折光，故較曜變與油滴瑰麗；在技術層次上，鋅結晶的形成比鐵結晶更困難﹘ ﹘它的燒成溫度高達攝氏一三○○度，只要誤差超過五度，即使之前已經形成了結晶的種子，也發不出結晶花來。