Aggregate habits
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Wheat Sheaf – Aggregates resembling hand-reaped wheat sheaves
Common examples include: stilbite Read more.
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Tabular/Blocky/Stubby – More elongated than equant, slightly longer than wide, flat tablet-shaped
Common examples include: feldspar, topaz, vanadinite Read more.
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Stellate – Star-like, radial aggregates radiating from a “star”-like point to produce gross spheres (crystals are not or weakly separated and have similar lengths)
Common examples include: pyrophyllite, aragonite, wavellite, “pyrite suns” Read more.
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Stalactitic – Forming as stalactites or stalagmites; cylindrical or cone-shaped. Their cross-sections often reveal a “concentric” pattern
Common examples include: calcite, chrysocolla, goethite, malachite Read more.
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Rosette/Lenticular – Platy, radiating rose-like aggregate (also lens shaped crystals)
Common examples include: gypsum, baryte, calcite Read more.
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Reticulated – Crystals forming net-like intergrowths
Common examples include: cerussite Read more.
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Radial/Radiating/Divergent – Radiating outward from a central point without producing a star (crystals are generally separated and have different lengths)
Common examples include: atacamite, stibnite Read more.
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Plumose – Fine, feather-like scales
Common examples: aurichalcite, boulangerite, mottramite Read more.
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Platy – Flat, tablet-shaped, prominent pinnacoid
Common examples include: wulfenite Read more.
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Pisolitic – Rounded concentric nodules often found in sedimentary rocks. Much larger than oolithic
Common examples include: bauxite, gibbsite Read more.
