Translucent porcelain is porcelain thin and vitrified enough to allow light to pass through it when held up to a lamp or window. Translucency is one of the defining qualities that separates true porcelain and bone china from opaque earthenware and stoneware, and it was a key goal for European potters seeking to match Chinese wares.
The degree and colour of translucency vary with the body and can help with identification. Chinese hard-paste porcelain typically shows a cool, slightly bluish or greyish light, while early English soft-paste porcelains may show a warm or greenish tone, and some include small brighter spots known as moons, caused by air bubbles in the paste. English bone china, developed at the end of the eighteenth century, is especially white and translucent. Exceptionally thin wares, such as Chinese and Japanese eggshell porcelain and fine Belleek, display translucency to a remarkable degree. Collectors and dealers often use a small torch to examine translucency, which can also reveal hidden cracks, firing flaws and restoration, since filled areas and overpainting usually appear darker or opaque against the surrounding glowing body.
