All of the ceramics made in the West for thousands of years were made from clays tht
contained ferric and other minerals that colored the final product. It was a long time before
Europeans were able to learn the secret and find kaolin to copy the Chinese porcelain.
"Porcelain

Porcelain is a hard, translucent ceramic which originated in China in
the 7th or 8th century A.D.. True porcelain is a hard paste which
involves the use of white china clay (kaolin). Porcelain was highly
desirable on the Continent, so much so that countries were desperate
to discover the secret of its production. The consequent rivalry in
Europe resulted in rulers pouring money into speculative ventures.
Grand Duke Francesco I founded the Medici factory in Italy in the late
16th century - the first European factory to produce soft-paste porcelain
of which examples are known today. Soft-paste porcelain was an
imitation of hard paste in which a variety of ingredients were used to
replace that unknown quantity, kaolin. Although Böttger discovered the
secret of true porcelain in 1708 (which he went on to produce at the
famous Meissen factory), France was not to discover high enough
quality deposits of kaolin until well into the 18th century. Thus, whilst
the secret of hard paste diffused to centres such as Vienna and Doccia
(just outside Florence), French factories such as St. Cloud and, later,
Sèvres, produced the most exquisite soft-paste porcelain. Sèvres did
go on to locate suitable kaolin, producing hard-paste porcelain, in
tandem with soft paste, between 1768 and 1800."
"