Cobalttoindigo

Cobalttoindigo is a color concept used to describe a family of blue-to-indigo hues associated with cobalt-based pigments and indigo. It is not a single chemical compound or a standardized pigment, but an informal label applied in art, design, and color science to denote a continuum between cobalt blue and indigo.

In pigment terms, cobalttoindigo encompasses dyes and pigments that display blue-violet shifts when mixed with indigo or when layered with glaze. Cobalt in its blue forms provides a bright, lightfast base, while indigo or near-indigo components deepen the tone. The resulting shade can vary from medium cobalt blues to deep violet-blues depending on concentration and medium. In digital color, cobalttoindigo is represented as a gradient or range bridging blue and indigo hues, rather than a fixed color.

Production methods: In traditional painting, artists may create CTI-like tones by blending cobalt blue pigments with indigo, ultramarine, or Prussian blue, or by applying successive glazes to shift the perceived hue toward indigo. In textiles or ceramics, cobalt-containing glazes can produce blue hues that move toward indigo with firing conditions and colorants.

Applications: CTI is used descriptively in color palettes, design briefs, and color grading to communicate a blue-to-indigo range without specifying a precise pigment.

Standardization and nomenclature: As an informal term, cobalttoindigo has no official definition in major color standards such as Pantone or HTML color names. Closest standardized references are individual pigments (cobalt blue) and indigo, plus digital color spaces.

Safety: Cobalt compounds can be hazardous if inhaled or ingested; appropriate handling and ventilation are recommended when using cobalt-containing pigments.

See also: cobalt blue, indigo, color gradient, color theory.