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Crystalline Particles

This is part of a guide to the identification of particles seen in samples of free particles. This file includes particles that exhibit obvious crystal structure.

Cubic Crystal Structure

These are isotropic particles. If sufficient faces are present then the some of the symmetries of Cubic crystal system and right angles should be evident.

Sodium Chloride From Plywood Sawdust Sodium Chloride Marine Aerosol Sodium Chloride Marine Aerosol Diamond Abrasive Ammonium Chloroplatinate

Hexagonal Crystal Structure

These are anisotropic particles. If sufficient faces are present then the some of the symmetries of Hexagonal crystal system and angles of 60 or 120 degrees should be evident.

Lead Iodide Crystals Zircon

Trigonal Crystal Structure

These are anisotropic particles. This is a subset of the hexagonal crystal system but it is sufficiently common to have its own classification. If sufficient faces are present then the some of the symmetries of Trigonal crystal system should be evident.

Tetragonal Crystal Structure

These are anisotropic particles. If sufficient faces are present then the some of the symmetries of Tetragonal crystal system and right angles should be evident.

Ammonium Phosphate Monobasic

Orthorhombic Crystal Structure

These are anisotropic particles. If sufficient faces are present then the some of the symmetries of Orthorhombic crystal system and right angles should be evident.

Monoclinic Crystal Structure

These are anisotropic particles. If sufficient faces are present then the some of the symmetries of Monoclinic crystal system should be evident.

Sucrose Crystals (Granulated Sugar) Sucrose Crystals (Granulated Sugar)

Triclinic Crystal Structure

These are anisotropic particles. If sufficient faces are present then the some of the symmetries of Triclinic crystal system should be evident.

Irregular Shape

These particles tend to be glasses, slags, or crystals of the cubic crystal system that lack any cleave plane, garnet for example.