mineral

Milky Quartz Geode Fragment

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Cloudy white (milky) to translucent; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Cloudy white (milky) to translucent
Luster: Vitreous to greasy

Identified May 16, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Cloudy white (milky) to translucent; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed from hydrothermal solutions or the cooling of silica-rich fluids within cavities of host rocks. This specimen appears to be a fragment of a small geode or vug, likely from the Cenozoic or Mesozoic era depending on the source locality.

Uses & applications

Used in glass making, abrasive materials, jewelry (as cabochons or beads), and as popular collector specimens for decorative display.

Geological facts

Milky quartz gets its characteristic white color from microscopic inclusions of gas or liquid trapped during the crystal's growth. It is the most common variety of crystalline quartz.

Field identification & locations

Identified in the field by its hardness (scratches glass), white cloudy appearance, and lack of cleavage. Common in many geological environments worldwide, particularly in Brazil, USA, and Namibia. Collectors should look for well-defined crystal faces on the inner surface.