Mullite

Mullite

Frequency	common
Hardness	6-7
Density	3.11
Chemical Formula	(Al2O3)3(SiO2)2

Mullite is the "rock" produced by ceramic work:

Uses

Primary

• Structural material

Secondary

• Filler for ceramics

Natural occurrence

• Mullite does occur naturally

Production

from kaolinite

by firing

Allotropes

• Platelet mullite is stable at temperatures below 1300°C. At temperatures above 1400°C it transforms into needle mullite
• Needle mullite is stable from low temperatures through its melting point of 1840°C