RED EARTH · CURATED PAINT RECIPE

How to mix rust paint

A dark iron-oxide red-orange for weathering, brick, leather, soil, and autumn subjects.

STARTING ANSWER5 Burnt Sienna + 1 Cadmium Red Medium + 1 Yellow Ochre + 0.25 Ultramarine BlueAdd ochre for fresh orange rust, sienna for classic iron oxide, or blue and umber for old dark corrosion.Mix #A94F32 with my paints →
Mixora IT editorial recipeUpdated September 24, 2026Estimated starting point

STARTING MIX

5 : 1 : 1 : 0.25

Use one consistent unit for every part. For the smallest fractions, scale the entire recipe up instead of estimating a partial drop.

5
Burnt Siennatransparent red earth
69%
1
Cadmium Red Mediumrestores red intensity
14%
1
Yellow Ochreoxide warmth
14%
0.25
Ultramarine Bluedarkens naturally
3%
Editorial starting point

Useful first test, with the claim kept honest

This recipe uses pigment behavior and color relationships to define a controlled starting point. It is not yet a named, brand-calibrated studio test. The target is an sRGB reference; your dried paint remains the deciding evidence.

See the evidence method and downloadable record →

PIGMENT LOGIC

Why this mixture works

Sienna already sits close to oxidized iron colors. Red and ochre expand its warm range, while a small blue addition provides dark crusted depth.

The displayed #A94F32 swatch is an sRGB target, not a promise that every brand will dry to the same color. Pigment identity, tint strength, opacity, medium, surface, and lighting remain part of the result.

BASIC-PALETTE ROUTE

Alternative recipe

Mix 3 parts warm red, 1 part yellow, and enough brown to produce an earth color rather than a clean orange.

Make the test useful

Apply the mixture on the same ground and at the same thickness planned for the final work. Label the wet ratio, wait for a complete dry-down, and compare in neutral light before adjusting.

CORRECTION MAP

How to adjust the result

Add ochre for fresh orange rust, sienna for classic iron oxide, or blue and umber for old dark corrosion.

Correct value first, then hue, then chroma. This order prevents a lightness error from turning into an unnecessarily complicated recipe.

WATCH FOR

Common mistakes

  • Using one flat rust color across every stage of weathering
  • Adding black to every shadow
  • Making the base too orange before adding earth pigments

SCALE THE BATCH

Keep fractional parts measurable

Choose a scale that turns the smallest addition into a unit you can repeat. The proportions stay identical.

Burnt Sienna1× batch: 5 parts2× batch: 10 parts5× batch: 25 parts
Cadmium Red Medium1× batch: 1 parts2× batch: 2 parts5× batch: 5 parts
Yellow Ochre1× batch: 1 parts2× batch: 2 parts5× batch: 5 parts
Ultramarine Blue1× batch: 0.25 parts2× batch: 0.5 parts5× batch: 1.25 parts

MEDIUM CHECKS

Translate the ratio into your material

  • Acrylic: compare only after full dry-down and keep film thickness consistent.
  • Oil: inspect both the thick mass tone and a thin application; transparent pigments can shift strongly with thickness.
  • Watercolor: mix by repeatable brush loads or drops, record dilution, and use the intended paper.
  • Miniature paint: match the primer, thinning, wash, and final varnish used on the model.

VERIFICATION PROTOCOL

What to record with the swatch

  1. Exact brand, range, color name, and pigment code where available.
  2. One measurement unit and the full ratio before any correction.
  3. Medium, surface, ground or primer, and application thickness.
  4. Wet observation, fully dry observation, light source, and date.
  5. The largest remaining value, hue, or chroma error and one next adjustment.

Print the studio test sheet →

THREE USEFUL VARIATIONS

Extend one successful base

  • Lighter: split off a sample and raise value gradually; inspect whether white also cools or dulls it.
  • Darker: use a related chromatic dark before reaching for black, then compare the undertone.
  • Quieter: reduce chroma with a prepared near-complement in very small steps so the value does not collapse.