Showing posts with label Porcelain. Show all posts
Showing posts with label Porcelain. Show all posts

Feb 7, 2014

Porcelain, Fine China, and Bone China

Exported Chinese porcelains were held in such great esteem in Europe that in the English language china became a synonym for porcelain.

Bone china is made from cow bone ash and other ingredients. The addition of animal bone ash gives bone china a warm color, while fine china is a brighter white. Bone china has a translucent quality compared to fine china. Fine china is made the same way, replacing bone with kaolin clay. 

Spone china - American artist Charles Krafft replaced cow bone ash with human bone ash, retrieved from a crematorium.

Porcelain is fired at a higher temperature and is much harder. Porcelain gets its name from old Italian porcellana (cowrie shell) because of its resemblance to the translucent surface of the shell. The raw materials are finely ground, cleaned, formed in a mold, and then fired.

If the temperature is high the finished product is more durable and known as porcelain. If it’s fired at a lower temperature it becomes fine china. Fine china is much softer than porcelain, making it suitable for plates and cups. Porcelain is strong enough and durable enough for a wide range of products, such as electrical insulators and toilets. Bottom line, all china is porcelain, but not all porcelain is china.

Nov 13, 2012

Crowns While You Wait

Instead of making a mold and sending it to a lab for scanning, dentists are now using a small camera to scan misshapen teeth. The digitized scan is then sent to an on-site milling machine that carves a crown from a block of porcelain. After preparation the crown is ready to be implanted.

The whole process is not much different than currently done. The area is numbed, and the dentist drills the tooth to shape it for the crown. Then the dentist uses a tiny camera to create a three-dimensional image of the drilled tooth. A computer program uses that to construct an image of what the tooth will look like with the crown in place. The image is transmitted to a machine on site mills the crown which is then glued on in the same process currently used.

Currently, the process is in use by about 10% of dentists, but will be used by more as the price of equipment comes down.

Oct 7, 2010

Chinese Inventions

Did you know the Chinese invented making silk from the cocoons of certain caterpillars. They also invented the compass, gunpowder, porcelain, wheelbarrow, paper, and early computer called an abacus. This was a simple calculator using beads which were moved along wires.

Others, including the Egyptians, Greeks, Romans and Japanese also used it to perform arithmetic problems. It can be used to add, subtract, multiply, and divide, and to calculate square roots and cube root. The abacus is still in use today.