1. A process for identifying minerals or crystals; a small rod is coated with a powdered form of the substance and subjected to suitably modified X-rays; the pattern of diffracted rings is used for identification
   - powder photography, powder technique

Derived forms: powder methods

Type of: photography

• optic
• optic axis
• optic chiasm
• optic chiasma
• optic cup
• optic disc
• optic disk
• optic nerve
• optic radiation
• optic tract
• optical
• optical aberration
• optical activity
• optical art
• optical bench
• optical character recognition
• optical condenser
• optical crown
• optical crown glass
• optical density
• optical device
• optical disc
• optical disk
• optical fiber
• optical fibre