MHH88CD3: On a matrix formed by the “frailesca” rock which is typical of the Almadén area, there are several cavities which have developed Cinnabar crystals, one of them clearly dominant with the predominant forms of the rhombohedron, with curved edges, extraordinarily lustrous and deep carmine-red. They are associated with small Calcite crystals and droplets of Mercury scattered in the matrix, plus tiny lustrous Pyrite crystals.
A classic association for the now extinct Las Cuevas Mine, in the Almadén mining district, although, unlike most specimens from this mine, the crystal is sharper and redder than what used to come out there.
Las Cuevas Mine, Almadén, Comarca Valle de Alcudia, Ciudad Real, Castilla-La Mancha  Spain

Specimen size: 6.7 × 4.9 × 3.1 cm = 2.64” × 1.93” × 1.22”

Main crystal size: 1 × 0.9 cm = 0.39” × 0.35”