Also known as the isometric system. All three axes are of equal length and intersect at right angles. Based on a square inner structure.
Crystal shapes include:
- Cube (diamond, fluorite, pyrite)
- Octahedron (diamond, fluorite, magnetite)
- Rhombic dodecahedron (garnet, lapis lazuli rarely crystallises)
- Icosi-tetrahedron (pyrite, sphalerite)
- Hexacisochedron (pyrite).
Common Cubic Crystals: