
Baryte with Cerussite from Morocco

Baryte with Galena and Hematite from Poland

The unit cell of barite
'Barite' (
BaSO4) is a
mineral consisting of
barium sulfate. It is generally white or
colorless, and is the main source of
barium. 'Baryte' is the British spelling, and the mineral is also called 'heavy spar'. The radiating form, sometimes referred to as Bologna Stone, attained some notoriety among
alchemists for the
phosphorescent specimens found in the
1600s near
Bologna, Italy by one Mr.
Vincenzo Cascariolo. Its
Mohs hardness is 3, the
refractive index is 1.63 and it has a
specific gravity of 4.3-5. Its
crystal structure is
orthorhombic.
Barite commonly occurs in lead-zinc veins in
limestones, in hot spring deposits, and with
hematite ore. It is often associated with the minerals
anglesite and
celestine.
The name barite is derived from the
Greek word ''βαρύς'' (heavy). In
commerce, the mineral is sometimes referred to as "barytes." The term "primary barite" refers to the first marketable product, which includes crude barite (run of mine) and the products of simple beneficiation methods, such as washing, jigging, heavy media separation, tabling, flotation, and magnetic separation. Most crude barite requires some upgrading to minimum purity or density. Barite that is used as an aggregate in a "heavy"
cement is crushed and screened to a uniform size. Most barite is ground to a small, uniform size before it is used as a filler or extender, an addition to industrial products, or a weighting agent in
petroleum well
drilling mud.
Barite is used in the manufacture of paints and paper. Although barite contains a "heavy" metal (barium), it is not considered to be a
toxic chemical by most governments because of its extreme
insolubility.
External links

Large barite crystals from Nevada, USA
★
mindat page for Barite
★
webmineral page for Barite
★
History of the Bologna stone