On the top you can see the color difference. The other porcelain is made from a low TiO2 mix of typical North American kaolins, feldspars and bentonites. Bottom with a light inside: Polar ice on the left is far more translucent. Yet it is not overly mature, it resists fired warping remarkably well. And it is also more plastic (which seems impossible). There is a secret to the translucency that goes beyond the fact that it employs New Zealand kaolin and the percentage of feldspar it has. But I cannot tell you. But if you read this site carefully you will discover it in the most unlikely place!
A highly sought after property in porcelain, they are fired close enough to melting to pass considerable light. It can be very difficult to fire translucent ware without it warping.
Standard porcelains used by potters and for the production of sanitary and table ware have surprisingly similar recipes. But their plasticities vary widely.