Ultramarine Violet

Overview

Ultramarine violet is the purple member of the ultramarine pigment family, sitting between ultramarine blue and ultramarine pink on the colour wheel. Like its siblings, it is a synthetic sodium aluminum sulfosilicate — the deep violet hue comes from specific processing conditions applied to the same base chemistry. The result is a rich, cool-toned purple that reads as true violet in most formulas.

The stability profile is identical to the rest of the ultramarine family: excellent lightfastness, full heat stability through normal cosmetic processing, and strong alkali resistance. The one weakness is acid sensitivity — below approximately pH 4, the crystal structure degrades, the colour fades to grey-brown, and hydrogen sulfide is released. This limits its use to formulas at pH 4 and above.

Ultramarine violet is popular in eye shadows, mineral makeup, and soap. In melt-and-pour soap (pH 7-8) it performs well. In cold-process soap (pH 9-10) it also holds up, though some makers report slight colour shifts during saponification depending on fragrance oils used alongside it. The pigment is a workhorse for anyone building a mineral colour palette — pair it with ultramarine blue for a deep navy, with ultramarine pink for berry tones, or use it alone for a clean purple.

What it does in a formula

Ultramarine violet provides opaque-to-semi-opaque purple colour. The tone is a true cool violet — not a warm plum and not a blue-purple, but right in the middle. Because it is an inorganic mineral pigment, it does not bleed or migrate, which makes it reliable in pressed powders and soap swirls alike.

The particle size is similar to the other ultramarines (typically 1-5 microns), fine enough for smooth application in pressed cosmetics but not so fine that it becomes transparent. At low concentrations it reads as a soft lavender; at higher concentrations it gives a saturated violet.

How to use

Pre-disperse in a small amount of oil (for anhydrous products) or glycerin (for water-based products) before adding to the main batch. As with all mineral pigments, skipping this step results in streaks and undispersed specks.

No special temperature handling required — ultramarine violet is heat stable well above any cosmetic processing temperature.

Usage rates by product type:

• Pressed eyeshadow: 2-15% (blended with mica or sericite base)
• Mineral blush (cool-toned): 1-5% (often combined with ultramarine pink)
• Cold-process soap: 0.5-1.5 tsp per pound of oils
• Melt-and-pour soap: 0.25-1%
• Bath bombs: 0.5-2%
• Loose mineral cosmetics: 1-10%
• Lip products: 1-5% (EU approved; FDA does not approve ultramarines for lips)

Best for / Worst for

Best for: eyeshadow, mineral colour palettes, soap (especially melt-and-pour), bath bombs, any decorative cosmetic at pH 5 or above where you need a true violet.

Worst for: any product below pH 4 (AHA formulas, low-pH vitamin C serums, acid toners), formulas requiring a warm plum or magenta (this is a cool violet), transparent gels or serums where you need a dissolved colourant rather than a dispersed pigment.

Common pitfalls

Acid degradation. Same rule as all ultramarines — below pH 4, the pigment breaks down and releases hydrogen sulfide. Always verify the pH of your finished formula. Soap, bath products, and powder cosmetics are all safe. Acidic skincare is not.

Colour shifts in cold-process soap. Some fragrance oils and certain lye concentrations can temporarily shift ultramarine violet toward blue or grey during saponification. The colour usually recovers during cure, but test a small batch first if you are using a new fragrance.

Treating violet and blue as interchangeable. They share an INCI name (CI 77007) but the hue difference is significant. A formula designed around ultramarine blue will look very different with violet swapped in. Always test.

Poor dispersion. Like all mineral pigments, ultramarine violet clumps when added dry. Pre-grind in oil or glycerin for even colour distribution.

Substitutes

• Manganese violet (CI 77742) — a warm-toned mineral violet, acid-stable, different chemistry entirely.
• Violet mica blends — pearlescent shimmer rather than matte opacity, popular in eyeshadow.
• Iron oxide blends (red + blue) — you can approximate a muted purple by blending, but the tone will be warmer and less clean than ultramarine violet.
• Chromium oxide green + ultramarine pink blend — a workaround for a muted purple in acidic formulas where ultramarine violet cannot survive, though the result is less vibrant.