metamorphic

Banded iron formation (iron-rich quartzite)

BIF; quartz (SiO₂) with hematite/magnetite (Fe₂O₃/Fe₃O₄), possibly amphibole or mica

AI-generated identification · may be incorrect

Dark gray-black and rusty-red layered specimen with metallic to earthy luster; likely fine-grained and very dense. Quartz-rich layers are about Mohs 7, while iron oxides are softer or may streak reddish-brown/black; no obvious cleavage is visible.

Identified September 11, 2026More metamorphic →

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Physical properties

Formation & geological history

Formed when silica-rich chemical sediments and iron minerals accumulated in ancient oceans, then lithified and metamorphosed. Most BIFs are Precambrian, commonly roughly 2.5–1.8 billion years old.

Uses & applications

Iron ore when sufficiently rich; otherwise used as decorative stone, lapidary material, and a collector specimen. Value is generally modest unless the banding and polish are exceptional.

Geological facts

The red-brown bands are likely hematite or weathered iron minerals, while black bands may contain magnetite. A magnet test can help detect magnetite-rich portions.

Field identification & locations

The appearance is consistent with iron-rich metamorphic rock, plausible around Zambia’s Precambrian basement and mineralized belts near the reported region, though exact identification requires testing. Check for a magnetic response, reddish-brown streak, and hardness sufficient to scratch glass.