mineral

Druzy Quartz on Limestone

Silicon Dioxide (SiO2)

Hardness: 7 (Quartz crystals), 3 (Limestone matrix); Color: Transparent to white crystals on tan/gray rock; Luster: Vitreous to sparkling; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture).

Hardness: 7 (Quartz crystals), 3 (Limestone matrix)
Color: Transparent to white crystals on tan/gray rock
Luster: Vitreous to sparkling

Identified April 3, 2026More mineral →

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Physical properties

Formation & geological history

Formed through hydrothermal processes or groundwater precipitation where silica-rich fluids permeate cavities (vugs) within sedimentary host rocks like limestone or dolostone.

Uses & applications

Primarily used as decorative display specimens, for lapidary work in jewelry, and as a popular entry-level collectible for mineral enthusiasts.

Geological facts

The term 'druzy' refers to a coating of tiny crystals on a rock surface. These types of specimens are common in geode-rich regions and can sometimes form over millions of years as mineral-saturated water slowly evaporates.

Field identification & locations

Identifiable by the 'sugar-like' sparkle on a rougher rock base. In the field, look for hollow or crystal-lined cavities in weathered limestone outcrops.