Quarry
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A quarry is a place where rock and earth materials – such as limestone, marble, granite, gravel, and sand – are excavated. The operation of quarries is regulated in some jurisdictions to manage their
A Portland stone quarry on the Isle of Portland, England
An abandoned construction aggregate quarry near Adelaide, South Australia
An abandoned construction aggregate quarry with turquoise pond near Thouars, France
An abandoned stone quarry in Kerala, India
Gypsum
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Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO4·2H2O. It is widely mined and is used as a fertilizer and as the main constituent in many forms o
Gypsum from southwest France (27 × 22 cm)
Gypsum crystals are soft enough to bend under pressure of the hand. Sample on display at Musée cantonal de géologie de Lausanne.
Large gypsum crystals in Lechuguilla Cave's "chandelier ballroom"
Gypsum crystals in the Cave of the Crystals in Mexico (person at lower right for scale)