Mineralogy · Runs entirely in your browser · PyScript
Crystal System Identifier
Pick the axial-length relationship and the interaxial-angle relationship you observe (or already know from crystallographic data), and get the matching crystal system, its symmetry, and example minerals.
Axial lengths
a = b = call three axes equal
a = b ≠ ctwo axes equal, one different
a ≠ b ≠ call three axes different
Interaxial angles
α = β = γ = 90°all right angles
α = β = 90°, γ = 120°hexagonal setting
α = β = γ ≠ 90°all equal, none 90° (rhombohedral)
α = γ = 90°, β ≠ 90°one oblique angle
α ≠ β ≠ γ, none 90°all different, none 90°
Select lengths & angles
then click Identify system
The seven crystal systems are distinguished entirely by the relative lengths of, and angles between, their three (or four, for hexagonal) crystallographic axes.