Bone china is a special type of porcelain.
It is known for its whiteness, translucency, and high strength.
The important raw material used in bone china is bone ash.
Bone ash mainly contains calcium phosphate.
A porcelain body containing a significant amount of bone ash becomes more translucent and white.
In the given question, the porcelain contains minimum:
\[
25\%
\]
bone ash.
Such a white translucent porcelain is called:
\[
\text{Bone china}.
\]
Belleek china is another type of fine porcelain.
Alumina porcelain contains high alumina.
Cordierite porcelain is based on cordierite composition and is known for thermal shock resistance.
Hence, the correct answer is:
\[
\text{Bone china}.
\]