mineral

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to tan/yellow (due to iron oxide staining); Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Milky white to tan/yellow (due to iron oxide staining)
Luster: Vitreous to greasy

Identified March 2, 2026More mineral →

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Physical properties

Formation & geological history

Forms in a wide range of geological environments, most commonly from the cooling of silica-rich magma or through hydrothermal vein deposits. This specific specimen appears to be a weathered piece of vein quartz, likely millions of years old.

Uses & applications

Used in the manufacture of glass, ceramics, and electronics (due to piezoelectric properties). In this raw form, it is used for gravel, landscaping, or as a common collector's specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is clear, but impurities like iron can turn it yellow (citrine) or create the surface staining seen on this specimen.

Field identification & locations

Identify in the field by its hardness (it will scratch glass) and lack of cleavage. It is found globally in almost all rock types. For collectors, look for hexagonal crystal terminations which add value.