Perlitic Structure

A perlitic structure in volcanic rocks consists of small concentric cracks, along which the rock readily breaks down, yielding rounded pearl-like fragments. The phenomena is found in some pitchstones and obsidians.

Related terms:

• Sedimentary Structure
• Mineral Structure
• mortar structure
• collapse structure
• primary structure
• flaser structure
• imbricate structure
• posthumous structure
• thin-skinned structure
• thick-skinned structure