mercallite

mercallite

[mər′kal‚īt]
(mineralogy)
KHSO4 A colorless or sky blue, orthorhombic mineral consisting of potassium acid sulfate; occurs as stalactites composed of minute crystals.
References in periodicals archive ?
Acid sulfate alteration is observed near to the La Olleta crater in the NRV; there, a paragenesis of amorphous silica, quartz, sulfur, alunite, mercallite and cristobalite was identified by XRD.