mineral

Stalactitic Calcite

Calcite (Calcium Carbonate, CaCO3)

Hardness: 3 on Mohs scale; Color: Creamy white to pale yellow; Luster: Vitreous to pearly; Crystal structure: Trigonal/Rhombohedral (often occurring in aggregate microcrystalline forms); Cleavage: Perfect rhombohedral; Specific Gravity: 2.71

Hardness: 3 on Mohs scale
Color: Creamy white to pale yellow
Luster: Vitreous to pearly

Identified March 23, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the precipitation of calcium carbonate from dripping water in limestone caves or through hydrothermal activity. These specimens often form as stalactites or flowstone over thousands of years during the Holocene or Pleistocene epochs.

Uses & applications

Primarily used as decorative specimens for mineral collectors, educational displays, and occasionally in the manufacture of lime or cement in its bulk form.

Geological facts

Calcite is the most common mineral to show fluorescence under UV light. The word 'stalactite' comes from the Greek 'stalaktos', meaning 'dripping'. These specimens are often called 'cave popcorn' or 'speleothems' when found in cave environments.

Field identification & locations

Identify in the field by its distinctive 'dripping' shape and its reaction to cold dilute hydrochloric acid (it will fizz). Commonly found in karst landscapes, limestone caverns, and mineral veins in Mexico, China, and the USA. Collectors should look for undamaged tips and unique structural branching.

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