Corundum is one possibility, at 9 on the Moh's Scale, sometimes in brilliant shades of red, blue, and other colors, which can have high luster.
Corundum.
Corundum is in the trigonal crystal system.
Pure corundum is clear in color.
Diamond is the hardest mineral and is the only one that can scratch corundum. but in my opinion corundum will scratch corundum any mineral of the same hardness will scratch the other !
Corundum's luster is metallic.
Ruby (corundum) has a vitreous or glassy luster.
The luster of the sapphire is vitreous or adamantine.
Corundum is one possibility, at 9 on the Moh's Scale, sometimes in brilliant shades of red, blue, and other colors, which can have high luster.
Corundum.
Corundum is not magnetic.
Corundum ( (Al_2O_3) ) is hexagonal in crystal structure.
Ruby cannot be considered either as it is not an element. It is primarily made of corundum, which is a compound of aluminum (a metal) and oxygen (a nonmetal).
Corundum is used for jewlery
Sapphire is a mineral itself. It is the blue variety of the mineral corundum. Sapphire is a very hard mineral at a 9 on the Mohs scale of 1 - 10. Sapphires usually have a glassy luster which makes them perfect for jewelry. They can also be colors other than blue; however, sapphires are never red. The red variety of corundum is a ruby.
Red corundum is called ruby.
Corundum is aluminium oxide, Al2O3.