Nice black blende on quartz

Beautiful black blende on quartz from the Madan Bulgaria mine year 1996;

Dimensions: length 135mm x width 90mm x height 45mm.

Weight: 360g.

Chemical formula and composition: Blende, also known as sphalerite, has the chemical formula (Zn,Fe)S. It is mainly composed of zinc and sulphur, with iron often present in varying quantities.

Hardness on the Mohs scale: The hardness of sphalerite is between 3.5 and 4 on the Mohs scale.

Density: The density of sphalerite varies from 3.9 to 4.1 g/cm³. Density indicates how heavy a stone is in relation to its volume. The higher the density, the heavier the stone for a given size.

Colour and possible variations: Sphalerite can come in a wide range of colours, including yellow, brown, black, red and green. Iron-rich specimens are generally darker, often black.

Cleaning Blende

Clean sphalerite with warm water and mild soap. Use a soft brush to remove embedded dirt. Rinse well with warm water and dry with a soft cloth.