Cobalt Pigments

TerraChrom’s Cobalt Pigment Collection features historic inorganic mineral colourants prized for their exceptional lightfastness, alkali resistance, and permanence in lime-based paint systems. Cobalt pigments marked a major turning point in architectural and fine art painting by providing stable, reliable alternatives to traditional ultramarine and smalt.

Etymology
The term cobalt has been used in pigment making since the early 19th century. The name derives from the German word Kobalt, meaning “mining spirit,” a reference to early miners’ experiences with cobalt-bearing ores.

Cobalt in Artistic Painting & Traditional Paint Making

Cobalt pigments have played a foundational role in the development of permanent blue and green colourants for both fine art and architectural finishes.

Before the 19th century, artists relied heavily on natural ultramarine (derived from lapis lazuli) or smalt—materials that were either prohibitively expensive or prone to fading, particularly in oil and lime-based paints. This changed in 1802 when French chemist Louis Jacques Thénard developed Cobalt Blue (PB28) by calcining cobalt oxide with alumina, creating one of the first modern synthetic mineral pigments with exceptional stability.

Produced by calcining cobalt oxide with mineral compounds at high temperatures, cobalt pigments form crystalline structures that offer subtle granulation, atmospheric tonality, and long-term durability in applications such as:

• Limewash and fresco

• Casein paint

• Silicate paint

• Oil and tempera

• Decorative mineral coatings

Ideal for breathable mineral finishes, TerraChrom cobalt pigments provide consistent colour performance for both interior and exterior use.

Why Artists Use Cobalt Pigments

Cobalt-based pigments are valued for their:

• Outstanding lightfastness

• Resistance to UV degradation

• Stability in alkaline environments (lime, fresco)

• Compatibility with traditional binders

• Subtle granulation and mineral matte quality

• Long-term colour permanence

Unlike many modern organic pigments, cobalt minerals remain among the most lightfast inorganic colourants available to artists, conservators, and architectural finishers. Their moderate opacity, mineral refractive qualities, and atmospheric depth create effects that cannot be replicated with synthetic dyes or petrochemical alternatives.

Pigments Available in This Collection

This collection includes the following artist-grade cobalt pigments:

• Cobalt Blue (PB28) – Turquoise Blue, Cobalt Blue Effervescent, SP Blue Cobalt

• Cerulean Blue (PB35) – Cyclades Blue, Sapphire Blue, Gallic Blue, Gascony Blue

• Cobalt Green (PG26) – Amazonite Blue Green

Tip: Cobalt pigments tend to appear more opaque in water-based techniques.

Handling & Safety Notes

When working with cobalt pigments in powder form:

• Avoid generating airborne dust

• Use local ventilation

• Wear a dust mask or respirator (P95 / P100)

• Avoid ingestion and prolonged skin contact

• Wet-mix where possible

Once dispersed into a binder such as lime, silicate, oil, or casein, pigment particles are immobilized within the matrix. Cobalt pigments are insoluble, calcined mineral colourants. While inert and stable in cured paint films, appropriate dust protection is recommended when handling the dry powder.

* Pigments are shipped in bags or containers depending on size and packaging options.
** Colours shown are for reference only. Actual colours may vary depending on screen settings, base material, and application method.