Posted in Kafevend Blog
What makes a cup? Bone china
Having presented an abbreviated history
and subsequently how hard and soft paste porcelain are made
, today we round off the trilogy with a piece on bone china- the best choice for your teas and coffees!
Bone china is a type of soft paste porcelain- however, unlike most other soft paste formulations, bone china is in fact the strongest of the various porcelains. That it can maintain this strength whilst also being formed into delicately wrought items is testament to its superior properties. Thanks to its strength and fine form, bone china is the most popular form of porcelain in the world.
Bone china is traditionally made up of two parts bone ash, one part kaolin and one part China or Cornish stone. The use of bone in porcelain production was the invention of Thomas Frye, who developed the mixture at his porcelain factory near Bow, in East London back in 1748. Unfortunately for him, the vagaries of the market did not go his way. Despite its quality rivalling that of European and Chinese imports, it was not a success for him. Success instead lay with Josiah Spode and his son Josiah II. Josiah began producing bone china at the end of the 18th century in Stoke-on-Trent, at first calling it Stoke China before settling on bone china, the name which has stuck ever since.
Back to the start
Amongst his achievements with bone china was the development of transfer printing first devised earlier in the century. Instead of untold hours of painting the decorations on to each and every item, hugely eloborate pictures and patterns could be applied in a fraction of the time by using engraved rollers. One of the most famous designs to come from this era is the blue and white willow pattern, which has no doubt graced your own cupboards or those of someone you know!
Another of his developments was in calcining the bone separately to the rest of the materials, unlike Thomas Frye. The process of calcining the bone cleaned and sterilised it. Following this it was ground down into a fine powder known as bone ash. When fired as part of the body the bone then produces calcium crystals, lending the finished product its strength. For those ethically minded amongst you, you'll be glad to know that these days a synthetic replacement is most commonly used!
Bone china was exclusively made in Britain for almost two centuries following its invention. Its production finally began to spread to other countries in the middle of the 20th century, heading back to the East where it had originated. Many countries in Asia now make bone china including Japan, India and, rather fittingly bringing the story back around full circle, China itself.
ReferencesSpode museum trustBone china