Can also be compact, granular, radially fibrous and massive. Its massive forms can be layered, coralloid, pisolitic, oolitic, globular, stalachtitic and encrusting. Aragonite is a constituent of many species' shell structures. A layered sedimentary marble like formation is called Mexican Onyx and is used for carvings and ornamental purposes. Calcite pseudomorphs of aragonite crystals and formations are common.
Fracture is subconchoidal.
Streak is white. Associated Minerals include gypsum , barite , smithsonite , malachite , calcite , serpentine , sulfur , celestite , zeolites , quartz , clays , dolomite , limonite , chalcopyrite and wulfenite among many others. Best Field Indicators are crystal habits, single plane of cleavage and reaction to acid.