What Is Interfacial Angle in Geology

The internal or dihedral angle between two faces of a crystal. It is also the ‘angle of dip’ between faces.

How do you find an interfacial angle?

Interfacial angles can be measured using a contact goniometer or more precisely using a reflection goniometer. See Klein & Hurlbut’s figure 2.40. The interfacial angle between two faces of a mineral crystal is identical for all crystals of the same mineral that exhibit the corresponding two faces.

What are interfacial angles in crystals?

interfacial angle In crystallography, the angle subtended by the normals to two crystal faces. It is not the external angle observed or the internal angle between them; it is, however, 180° minus the internal angle. A goniometer is used to measure interfacial angles.