mineral

Druzy Chalcedony/Quartz on Fluorite core

Silicon Dioxide (SiO2) on Calcium Fluoride (CaF2)

Hardness: 7 (quartz coating) / 4 (fluorite core). Color: translucent greyish-blue or white. Luster: Vitreous to sparkling (druzy). Crystal structure: Hexagonal/Trigonal microcrystals coating Cubic cores. Specific Gravity: ~2.65.

Hardness: 7 (quartz coating) / 4 (fluorite core)
Color: translucent greyish-blue or white
Luster: Vitreous to sparkling (druzy)

Identified April 4, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydro-thermal veins where silica-rich fluids precipitate over pre-existing minerals. Often occurs as epimorphs or pseudomorphs where the inner mineral creates the shape for the outer coating.

Uses & applications

Decorative display, metaphysical collecting, lapidary use, and occasionally used in jewelry as organic-shaped pendants.

Geological facts

This specific shape is often referred to as a 'sugar' coating. When quartz replaces the original mineral entirely, it is called a pseudomorph. If it just coats it, it is a druzy overgrowth.

Field identification & locations

Identify by its 'sparkly' surface and the ghost-like shapes of the original crystals (likely fluorite cubes) underneath. Frequently found in regions like Morocco, India, or the Southwestern United States.

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