mineral / sedimentary
Hematite / Jasper
Iron(III) oxide (Fe2O3) in Quartz (SiO2)
Hardness: 6.5-7 (Mohs), Color: Reddish-brown, yellow-brown, Luster: Dull to earthy, Crystal Structure: Trigonal/Microcrystalline, Specific Gravity: 2.6-5.3 depending on iron content
- Hardness
- 6
Identified More mineral / sedimentary →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6.5-7 (Mohs), Color: Reddish-brown, yellow-brown, Luster: Dull to earthy, Crystal Structure: Trigonal/Microcrystalline, Specific Gravity: 2.6-5.3 depending on iron content
Formation & geological history
Formed through the accumulation of iron-rich sediments or via hydrothermal replacement in metamorphic environments, often part of banded iron formations (BIFs).
Uses & applications
A major ore of iron when found in high concentrations; also used for decorative carvings, lapidary work, and pigment production.
Geological facts
The red and brown color is specifically due to the oxidation of iron within the silica matrix, essentially acting as a 'natural rust' pigment within the stone.
Field identification & locations
Identify in the field by its high density relative to other stones and use a streak test on unglazed porcelain; iron-rich specimens will leave a reddish or brownish streak.
More like this
Other mineral / sedimentary specimens
Limonite (Ironstone Concretion)
Limonite (FeO(OH)·nH2O)
mineral/sedimentary
Jasper
Silicon dioxide (SiO2)
Mineral / Sedimentary
Quartz Geode
Silicon Dioxide (SiO2)
Mineral / Sedimentary
Jasper Pendant
Chalcedony (Quartz) - SiO2
Mineral/Sedimentary
Jasper
Silicon dioxide (SiO2)
Mineral/Sedimentary
Jasper
Silicon dioxide (SiO2)
Mineral / Sedimentary