Apatite Vs. Corundum

Apatite is a popular mineral group composed of a group of phosphates.^[1] Corundum is a very popular mineral and its chemical composition is aluminum oxide.^[2]

Quick Facts on Differences of Apatite and Corundum

For a quick recap of the differences apatite and corundum:

• While both apatite and corundum can be translucent or transparent, corundum can be opaque.
• While both apatite and corundum is hexagonal, in terms of crystallography, corundum can be trigonal.
• For chemical formulas, apatite can be Ca5(PO4)3(F, Cl or OH) while corundum is Al2O3.
• While both apatite and corundum is vitreous, in terms of luster, corundum can be adamantine.
• While both apatite and corundum can be commonly red, corundum is often blue, brown, green or pink.
• Apatite's rarity is less rare than corundum.
• Apatite's hardness is lower than corundum - apatite is 5 and corundum is 9 on the Moh's scale.
  • Apatite can be scratched by glass (5.5) or quartz (7) while corundum can not be.

Quick Facts on Similarities of Apatite and Corundum

The similarities of apatite and corundum include:

• Apatite and corundum both streak white.

Summary of Apatite

Apatite is a mineral that is commonly found in igneous, metamorphic, and sedimentary rocks. It is made up of calcium phosphate, which is the same mineral that makes up our teeth and bones. Apatite can be identified by its green, blue, or yellow color, and its hardness of 5 on the Mohs scale. It can also be identified by its crystal structure, which is hexagonal.

Summary of Corundum

Corundum is a mineral that is commonly found in metamorphic and igneous rocks. It is composed of aluminum oxide and can be identified by its hardness and crystal structure. Corundum has a hardness of 9 on the Mohs scale, making it one of the hardest minerals known to man. Its crystal structure is hexagonal, with six-sided prisms and pyramids that form a beautiful and distinctive crystal habit.

Table Comparison of Apatite vs Corundum