Ironstone
“Sediment stained with iron”
Sedimentary
Ironstone is an iron-rich sedimentary rock containing at least 15% iron, typically in the form of siderite, goethite, or hematite. It formed abundantly during specific periods of Earth's history and was a vital ore during the early Industrial Revolution.
Composition
siderite, goethite, hematite, chamosite, clay minerals, quartz
Where Found
Cleveland Hills (England), Lorraine (France), Mesabi Range (Minnesota, USA), Pilbara (Australia)
Mohs Hardness
4-5
Fun Fact
The Cleveland Ironstone of northeast England fueled the industrial boom of Middlesbrough, which grew from a hamlet of 25 people to a town of 90,000 in just 50 years.
Test Your Knowledge
Why was ironstone a major ore source during the early Industrial Revolution but is rarely mined today?
Related Specimens
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