Rublev Colours Barite uses the highest-quality white, natural barium sulfate ore. Its fine grind (4-micron median particle size), high specific gravity (4.4), and inertness make it ideal for grounds, making white paint in watercolor, casein, and egg tempera, and as an extender pigment in oils and alkyds.

Barite is a mineral consisting of barium sulfate. Due to impurities, the natural mineral is generally white or slightly colored. It is the primary source of barium. Baryte is the British spelling; the mineral is also called heavy spar. The radiating form of the mineral, sometimes referred to as Bologna Stone, attained some notoriety among alchemists for the phosphorescent specimens found in the 1600s near Bologna, Italy, by Mr. Vincenzo Cascariolo.

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, which is used as an aggregate in "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 commonly occurs in lead-zinc veins in limestone, hot spring deposits, and hematite ore. It is often associated with the minerals anglesite and celestine. While baryte is sometimes found with lead, zinc, and manganese, deposits exploited for industrial uses such as coatings are free from toxic metals. Our barite is from a natural source in the U.S. and does not contain heavy metals. Barite is mined in Canada, Mexico, and the United States in Arkansas, Missouri, Georgia, and Nevada. It is also prepared synthetically, called "blanc fixe," either by treating a barium salt solution with sodium sulfate or as a by-product in the manufacture of hydrogen peroxide.

Barite is unaffected by dilute acids and alkalis. It is compatible with all pigments and in all vehicles.

Barite absorbs 12 grams of oil per 100 grams of pigment. It readily mixes with oil and water to form a smooth paste.

Although barite contains a "heavy" metal (barium), most governments do not consider it a toxic chemical because of its extreme insolubility. Care, however, should be used in handling the dry powder pigment to avoid breathing the dust.

Rublev Colours Pigment: Barite

* Hunter Dry Brightness, L Value
** Spatula Rubout Method