To observe the surface morphology of natural and calcined
dolomite, the samples were initially covered with a thin layer of
gold (10 nm) using a sputter coater (SCD 050; Baltec, Liechtenstein),
and observed using a JEOL JXA-840A scanning electron
microscope (20 kV) under a vacuum of 1.33 106 mBar (Jeol,
Japan)