Are There Really Bones In Bone China?

Posted on April 14, 2019 by Maurice Robertson | 0 Comments

A Spode Bone China Saucer Dish - Circa 1810

When we speak of bone china, does it ever raise the question, however fleetingly, "I wonder if this cup I’m drinking from, actually contains bones"?  The short answer is "yes"!  But we can’t leave it there, so on to the long answer …..

Conventionally, the development of bone china is attributed to Josiah Spode (1754-1827), who introduced it in 1797, but like many stories, bone china goes back a lot further than that.

We must first acknowledge China as the first country to produce porcelain, a prototype or early type of porcelain, about the year 1000.  About 400 years later, examples of Chinese porcelain arrived in Europe.  From then on and right up until the early 18th century, the race was on to discover the “secret mystery” of how to make porcelain.

The earliest recorded attempts were in late 16th century Italy, in the Medici ruled city of Florence, where experimental porcelains were produced by mixing powdered glass with clay in an attempt to reproduce the tantalizing translucency of the Chinese examples acquired.

Further attempts were made in the late 17th century at Rouen in France, until porcelain, at last, was successfully made at Meissen during the first early years of the 18th century.  This was known as high fired or hard paste porcelain in the Chinese manner.

Up until the mid 18th century, there is no doubt that the most beautiful European porcelains were produced at the French factories, such as St Cloud, Chantilly and Mennecy.  Many are the writers who describe these porcelains as “delicious” and “luscious”, the French factories, some would say, peaking with the famous porcelains of Vincennes and on to Sevres in 1756.

These famous French porcelains were all soft paste, also known as “artificial porcelain” which was produced by the addition of powdered glass to china clay, as in the early Florentine, Medici porcelain.   Powdered glass was used as a substitute for feldspathic rock, also called “petuntse”.  This naturally occurring silicate fuses under a high temperature changing into a kind of natural glass.

However, it is not possible to completely outline the story of bone china without first looking at the development and contribution of English soft paste porcelain.

The first mention of soft paste porcelain, (1742), was by Thomas Briand, a speaker and member of the prestigious British Royal Society.  Briand delivered a paper on porcelain to The Society and it is now believed to have been based on the French, St Cloud formula.

The first English factory to produce soft paste porcelain in the French manner was Chelsea, established in 1743.  Chelsea, true to the French style, used powdered glass to produce its early, superb and now, incredibly rare porcelain.   

The two partners who established the Chelsea factory were Thomas Briand, (the same Thomas Briand who delivered the lecture to the British Royal Society) and a French silver smith, both of French Huguenots descent, hence the connection to St Cloud!

We now arrive at bone ash porcelain or the more widely known term “bone china”.

Bone china does indeed contain bones!  Lots of bones, usually cattle bones!  The raw bone, left after cleaning, is heated in a kiln to about 1000°c, at which temperature the bone is reduced to a fine white ash.  It is then finely ground with water before being blended with crushed feldspar and china clay.  Bone china, in fact, consists of a remarkable 50% bone ash, 25% feldspar and 25% of the finest china clay.            

Bone ash porcelain was first introduced at the London Bow factory circa 1750, with Chelsea following circa 1755.  The bone ash mix produced better molding properties and greater stability.  These factors substantially reduced kiln loss, which caused great problems for most of the 18th century factories.

Here is where we meet Josiah Spode I, who in 1767, after a seven year apprenticeship and a number of other partnerships, opened his own factory.  His son, Josiah Spode II, now having inherited his father’s factory, is attributed with the refinement and perfection of bone china.  (The Spode factory still stands on this very same site and holds the title of “the oldest porcelain producing factory still standing on its original site”).

Spode's great contribution was to experiment with and discover the ideal porcelain body.  In short, he took the standard hard paste porcelain mix of china clay and feldspar, based on traditional Chinese porcelain and added refined bone ash.  This process totally transformed the English ceramic industry and by the end of the 18th century, with one exception, no soft paste porcelain was made in England.

Bone china became and is now the standard English porcelain which has been an exclusive English product ever since.  Bone ash has rarely been used outside of England, with the US and European manufacturers preferring the hard paste porcelain in the Chinese manner.  It is the bone ash which gives bone china its strength and whiteness, with a remarkable translucency -  and there are no bones about that! 

©Antique Lamp Shoppe

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