sedimentary
Botryoidal Hematite (Iron Stone Conglomerate)
Hematite (Fe2O3) in sedimentary matrix
Hardness: 5-6.5 on Mohs scale; Color: Reddish-brown to dull black; Luster: Metallic to earthy; Crystal Structure: Trigonal (often appearing as rounded, grape-like clusters); Cleavage: None; Specific Gravity: 4.9-5.3
- Hardness
- 5-6
- Color
- Reddish-brown to dull black
- Luster
- Metallic to earthy
Identified More sedimentary →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 5-6.5 on Mohs scale; Color: Reddish-brown to dull black; Luster: Metallic to earthy; Crystal Structure: Trigonal (often appearing as rounded, grape-like clusters); Cleavage: None; Specific Gravity: 4.9-5.3
Formation & geological history
Formed through the precipitation of iron-rich minerals from aqueous solutions, often in sedimentary basins or as oxidation products of iron-bearing minerals. These concretions usually form in arid environments or within sandstones over millions of years.
Uses & applications
Primary ore of iron; also used as a pigment (ochre), in jewelry as polished stones, and as a popular mineral specimen for collectors due to its unique bubbly texture.
Geological facts
The name comes from the Greek word 'haima', meaning blood, because of its red color when powdered. Botryoidal comes from the Greek 'botrus', meaning a bunch of grapes, referring to its rounded external shape.
Field identification & locations
Identify in the field by its distinct grape-like rounded texture, high density for its size, and a characteristic reddish-brown streak when rubbed on unglazed porcelain. Commonly found in the American Southwest, specifically Utah and Arizona.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Shale or Slaty Mudstone
Argillaceous sedimentary rock
sedimentary
Chert Breccia
Brecciated Chert (Microcrystalline Silica)
sedimentary
Sandstone (Quartz-rich)
Arenite (SiO2)
sedimentary
Sandstone (with man-made markings)
Arenite (composed primarily of Quartz, SiO2)
sedimentary