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- Vesicular structure - possessing an abundance of air-bubbles formed by expanding gases before solidification.
- Pumiceous structure - a froth-like structure due to extreme vesiculation.
- Scoriaceous structure - a vesicular structure in mafic rocks
- Amygdaloidal structure - possessing amygdules or gas cavities filled with secondary minerals.
- Miarolitic structures - small openings in rocks, commonly lined with crystals.
- Perlitic cracks - onion-like cracks formed in glasses by contraction upon cooling.
- Expansion fractures - formed in surrounding grains when a mineral expands upon alteration.
- Flow structure - a planar structure produced by flowage during the middle- or late-stage of solidification.
- Fluidal structure - a similar structure characteristic of aphanitic rocks.
- Eutaxitic structure - a streaked appearance in volcanic rocks due to alternating layers of different material, color, or texture.
- Banded structure - composed of layers of different minerals. Characteristic of gabbros.
- Spherulitic structure - containing spherulites, spherical masses of acicular crystals radially arranged about a common center. Characteristic of glasses.
- Variolitic structure - similar to spherulitic, but in mafic rocks.
- Lithophysae - concentric arrangement of slightly different materials in what appears otherwise to be a homogeneous crystal.
- Zoning - a concentric arrangement of slightly different material in what appears otherwise to be a homogeneous crystal.
- Hourglass structure - a peculiar structure, somewhat resembling zoning observed in certain sections of crystals and giving the appearance of an hourglass.
- Reaction Rims - a peripheral zone of minerals formed around another mineral by reaction of the latter with the magma or adjacent minerals.
- Orbicular structure - containing rounded masses showing concentric shells usually of different mineral composition.
- Cavernous structures.