The Acid Test for Calcite and Dolomite
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Geologists test for the presence of carbonate minerals by placing a drop of dilute (10%) hydrochloric acid on a specimen. If a fizz (effervescence) occurs then the specimen contains carbonate minerals. The two most commonly encountered carbonate minerals are calcite and dolomite. Calcite will fizz strongly with cold hydrochloric acid, while dolomite must be powdered or tested with warm hydrochloric acid to produce a strong fizz. Other carbonate minerals will fizz with various levels of vigor.
Protective gloves, glasses, paper towels and immediate access to an eyewash station are recommended when acid testing is done.
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