All You Want to Know about Bone China
Bone china is also called as the king of ceramic , the most healthy ceramics , the most elegant ceramics .
However, we found that many customers feel novel about what is bone china and doubting is it really bone powder used in bone china products? Even if most regular customers have vague definition about bone china .
Therefore, in this article, we are going to discuss everything about bone china. Anyone who interested in this topic will get a full basic information they need to know about fine bone china.
1.what is bone china? What is bone china made of?
The word “china” clearly shows that the country is the “home of pottery and porcelain.” while bone china is a kind of porcelain.
Bone China, also called fine bone china, bone porcelain, is a type of ceramic that uses bone ash, clay, feldspathic material and kaolin as basic material.
Bone china needs to go through two times of firing, high temperature(1250℃) firing, which is also called biscuit firing, and lower temperature(1150℃) firing, also called glaze firing. For decorated bone china products, the firing process is even more complicated, which may reach 3-5 times firing .As decoration ,the bone china items can be painted in a variety of bright colour glazes or have CMYK decals applied to them.
Typical daily bone china tableware including bone china dinnerware, tea set, coffee set, cup and saucer set, mugs etc.
2.The features of the bone china
Holding a bone china cup in a dark place and put a torch inside it, you can see the light go through the bone china body, which is quite impressive.
- Milky white and Light weight
Bone china is known for its high level of whiteness and translucency. With bone ash added to the raw material, the bone china tableware gives a milky white color, it is also lighter than other ceramic products, these features make bone china getting more and more popular in the modern days.
Yet it is light, semi-transparent, it seems fragile, while it is the strongest porcelain. It’s wear-resistant features make it a favorable and top choice for high-end hotels, Casinos & Resorts, Upscale dining establishments, Corporate & Academic dining facilities and more.
After two times of firing and glazing, the surface of bone china tableware is very smooth, which makes it very easy to wash. This feature makes bone china dinnerware and tea sets favorable by housewives.
- ZERO percent of toxic elements like lead and cadmium
It is not enough just having an attractive appearance. The safety issue is the top topic people care about. After all, tableware is something we used to serve our food, and it’s very important it is not toxic to our health.
With zero lead and cadmium content, bone china is regarded as the safest tableware, with the bone ash ingredient in its raw material, it is beneficial for people’s health too, as the bone ash contains elements that are beneficial for peoples health.
3.About new bone china
First and foremost, new bone china is not bone china.
It is a concept created to gain more attention and a marketing strategy to sell porcelain at a higher price. In fact, it is just a kind of porcelain, but have some similar features like bone china.
3.1 What is new bone china
New bone china is in fact a kind of white porcelain, by adding mineralizer and calcium oxide(which has similar elements as bone ash) to the raw material, producing something that has some difference from the traditional porcelain in the aspects of firing temperature and deformability, absorption and transparency, thus forming a kind of porcelain which has similar appearance as bone china.
3.2 How to dustinguish bone china and new bone china
While New bone china might have a similar whiteness and smooth like bone china, it is quite differenced from bone china in the aspects of raw material and texture.
Bone china contains more than 36% of bone ash, while new bone china doesn’t have any bone ash added.
As mentioned, bone china formed by two times of firing, while new bone china, like other porcelain, formed by one-time firing.
Comparing to new bone china, bone china has a softer white appearance, higher transparency, and lighter. Its appearance is much better than new bone china.
Caused by the different material , times of firing ,the only advantage of new bone china is the price,compared to bone china items . New bone china products have much low cost than bone china products .
When international buyers ask for quote about bone china, if they are not careful enough, they may get in the risk of getting fake bone china items ,with lower prices .
Thus it is important to keep cautious when you are purchaing bone china items .
4.The progress of fine bone china .
A standard manufacturing progress of bone china entails the following stages .The each stage is handled with highly skilled craftsmanship to ensure the finest quality .
4.1 Mixing: A body mixture is made with bone china powder ,seldspar ,quartz ,kaolin and ball clay.Among all of the integredients ,bone powder ( about 40% to 45% of the mixture ) is the key ingredient that enhances whiteness and translucency of bone china .
4.2 Forming : forming methods vary depending upon the shapes regular round pieces like plates and bowls are generally formed on jiggers and such irregular pieces as pots and gravy boatts are cast in plaster molds .Oval ,square and rectangular pieces are ,moreover ,cast in two -parted plaster molds to stalilize the shapes .The formed bodies ,now called greenwares are lest to dry and finished with water sponging to gently remove scratches and scars from the surfaces .
4.3First Firing (biscuit ) : Differ from the conventiaonal porcelain making , the bone china ' first firing ,called biscuit, is carried out at a temperature of round 1200 to 1300 centigrade in the oxidizing atmosphere .This progress vitrifies the greenware and makes them durable ,white ,anf translucent .However,in order to achieve the best results within such specific temprature range ,the firing schedule muct be carafully controlled .Also ,about 20% shrinkage of the greenwares occuring at this stage is apt to cause deformation and cracking .In order to overcome this ,most pieces are placed on refractory setters ,called 'cranks ' .tp left them follow the profiles of the setters .Those irregular shapes pieces that the on- crank firing does not work are set in saggers.
4.4Glazing: Bone china glaze is a mixture of frit and kaolin .Because the biscuit ( the greenware after first -fired ) is nonabsorbent , the glaze needs to be applied by spraying .
4.5 Second firing ( glost ) : The glaze -coated biscuit are set in the saggers in orders to availd direct exposure to flames .The saggers are piled up on klin cars and sent in to tunner klins. When the temprature goes uo to around 1000 to 1200 centigrade in the oxidizing atmosphere ,the glaze melts ans fuses on to the biscuits .All glastwares coming out of the klins are strictly inspected and only a few can be passed on to the decarating atage .
4.6 Decorating : Bone China 's standard decorating mothods are spraying ,decal transferring ,gold finishing and hand painting .After the decoration ,pieces are fired at 700-800 centigrade again to make the pigments fuse in to the glaze -coatings ,Among the mentioned decorating methods ,hand-painting is applied only by proficient artisans .Also ,gold or platinum finishing is hand-blushed on to the pieces by well-skilled artisans when necessary .
5. How to mantain bone china products :
As we all know bone china products are expensive and exquisite, how to maintain bone china dinnerware, here are a few tips for you to follow:
5.1Hand wash, if you need to use dish-wash machine, make sure you choose machine with the function“porcelain or crystal”.
5.2Wash in clean water, with the temperature less than 80 Centigrade.
5.3 If the bone china product is gold grimed, don’t use in oven to prevent corrosion.
5.4 Wash PH should be 11-11.5.
5.5 Don’t put hot mugs directly into cold water, in case the sharply change of temperature damage the products.
5.6 If the product is scratched, polish it with tooth paste.
5.7 Use lemonade or vinegar to clean tea stain.
5.8 Don’t use it in the condition of dramatically temperature changing to avoid explode.
5.9 Don’t put it on fire directly.