Dolostone
“Limestone's magnesium cousin”
Sedimentary
Dolostone (or dolomite rock) is a sedimentary rock composed mainly of the mineral dolomite. It often forms when magnesium-rich groundwater alters existing limestone in a process called dolomitization, partially replacing calcium with magnesium.
Composition
dolomite (CaMg(CO₃)₂), calcite, traces of quartz
Where Found
Dolomites (Italian Alps), Niagara Escarpment (USA/Canada), Zambia, Spain
Mohs Hardness
3.5-4
Fun Fact
The stunning Dolomite mountain range in northern Italy — a UNESCO World Heritage Site — gave the mineral and rock their name.
Test Your Knowledge
What is the 'dolomite problem' that has puzzled geologists for decades?
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