Ironstone

About it

Heavy sedimentary rock rich in iron minerals such as goethite, hematite, siderite, or chamosite, rusty brown when weathered. It formed the Clinton ores of the Appalachians and the Jurassic ores of the Cleveland Hills, England.

Type

Rock (sedimentary)

Group

Sedimentary (chemical)

Streak

yellow-brown to red-brown

Lustre

dull, earthy

Colours

brown, rusty red, yellow-brown, dark grey

Transparency

opaque

Typical values: real specimens vary. For more, see mindat.org.