Nnukwu otu kristal alumina bụ kristal na-acha ọcha kristal kpụrụ site na ikpo ọkụ dị elu nke aluminom hydroxide ma ọ bụ alumina ụlọ ọrụ nwere ihe ịnweta pụrụ iche.
Flake alumina nwere ezigbo ihe eji eme ihe yana njirimara nhazi pụrụ iche.