7 Crystal system

The Seven Crystal System is a classification system in crystallography to classify crystals based on their geometric shapes.

Each system is defined by the relationships between the lengths and angles of the crystal axes.

Here are the seven crystal systems:

Crystals have differing amounts of symmetry and are placed , according to this, in one of seven major categories called systems. Crystals in the cubic system have the highest symmetry. The most symmetrical have 9 planes, 12 axes, and a center of symmetry. Crystals in the triclinic system have the least symmetry with only a center of symmetry or no symmetry at all.

Cubic/Isometric System

(The right image shows that) All three crystal axes (α, β, γ) are of equal length, and the angles between them are all right angles/90 degrees.

2. Tetragonal System

Two crystal axes (α and γ) are of equal length, and the third (β) is different. All angles are right angles.

3. Orthorhombic System

Along with Monoclinic and Triclinic system, all three axes (α, β, γ) are different lengths, and all angles are right angles.

4. Monoclinic System

Same as earlier, all three crystal axes are different lengths.

But two angles are 90 degrees, while the third isn't.

5. Triclinic System

Same as earlier, all three crystal axes are different lengths. But all three angles are different from each other.

6. Hexagonal System

There are 4 crystal axes, 3 of equal length and in the same plane at 120-degree angles. The fourth axis is perpendicular to the plane formed by the other three.