Question

are non-metals. +
Diamond, which is very hard and shiny, is a metal.
Aluminium is a non-metal​

Answer 1

Answer:

Diamond though is the hardest and most shiny substance on the earth but it is a allotrope of carbon which is a non metal. Hence Diamond is also a non metal.

Aluminium on the other hand is derived or extracted from bauxite which is a metal. Hence Aluminium is a metal.

Hope it is clear....................