Iron oxide pigments are among the oldest colourants in human history — they are the same compounds responsible for the reds, yellows, and browns in cave paintings that have lasted tens of thousands of years. That permanence is exactly why they are the preferred colourant for concrete casting. The colour does not fade in sunlight, does not wash out in rain, and does not react with the alkaline environment of cement the way organic dyes do.
For makers working in Jamaica and the Caribbean diaspora in the USA and Canada, iron oxides are also one of the few colourants that perform reliably in a hot, humid outdoor environment. They are mineral-based, chemically stable, and bond permanently into the concrete matrix during the curing process.
Shop Iron Oxide Pigments →The Colour Range
J.C. Epiphany stocks twelve iron oxide colours, covering the full spectrum from earth tones to saturated hues. Each is available for purchase individually for concrete casting and decorative concrete work.
Barn Red
Charcoal Grey
Coral
Dark Blue
Dark Green
Green
Honey Yellow
Light Blue
Mauve
Mustard Yellow
Squash Orange
Turquoise
How Much Pigment to Use — Concrete Use Rates
In concrete casting, iron oxide pigments are added to the dry cement mix before water is introduced. This ensures even distribution throughout the material rather than surface staining. The colour achieved depends on three factors: the pigment colour, the use rate, and the base cement colour — white Portland cement produces truer, more saturated colours than grey Portland cement.
| Desired Intensity | Use Rate (% of cement weight) | Notes |
|---|---|---|
| Subtle / pastel | 1% to 2% | Best on white Portland cement base. Results in soft, muted tones. |
| Medium / standard | 3% to 4% | Balanced colour depth. Most commonly used rate for decorative pieces. |
| Deep / saturated | 5% to 6% | Maximum recommended rate. Beyond 6%, additional pigment does not deepen colour and can weaken the concrete mix. |
Important — Do Not Exceed 6% in Concrete
Iron oxide pigment added beyond 6% of cement weight begins to interfere with the cement hydration process. The colour does not continue to deepen but the structural integrity of the cast can be compromised. For decorative pieces this may not cause visible failure, but the piece will be more porous and fragile than intended. Stay within the 1% to 6% range.
Using Iron Oxide Pigment in Concrete — Step by Step
Here is the plain, step-by-step method for colouring concrete with iron oxide pigment:
- Weigh your cement first. Pigment is dosed as a percentage of cement weight, so you need that number before anything else.
- Measure the pigment by weight. Use 1% to 2% for a soft pastel, 3% to 4% for a standard colour, and 5% to 6% for a deep, saturated shade. Never go above 6%.
- Mix the pigment into the dry ingredients. Add the powder to the dry cement and sand and blend thoroughly until the colour is even, with no streaks. Doing this dry is what gives colour that runs all the way through the piece.
- Add water and mix as normal. Bring the batch to your usual consistency. The colour will look darker while wet and lighten as it cures.
- Test a small batch first. Cast a small sample, let it cure, and check the dried colour before committing to a full pour — this is the only reliable way to judge the final shade.
- Cure slowly. Keep the cast damp and out of direct sun while it sets. Slow, even curing gives the truest, most consistent colour.
For white or pastel results, use white Portland cement as your base — grey cement mutes and darkens every colour you add to it.
These Pigments Are for Concrete Use Only
J.C. Epiphany iron oxide pigments are supplied for concrete casting and decorative concrete projects. They are not assessed, tested, or recommended for use in soap, cosmetics, or any skin contact product. If you are looking for colourants for handmade soap, those require cosmetic-grade ingredients that have been through appropriate safety assessment — a separate category of product entirely.
For concrete use, the pigments perform exactly as described throughout this guide — permanently, reliably, and without the fading or bleed that organic dyes produce in an outdoor environment.
Colour Mixing — Getting Shades Beyond the Range
Colour Mixing Guide
- Terracotta / rust — Barn Red + small amount of Honey Yellow. Adjust ratio to move warmer or cooler.
- Olive / khaki — Green + Honey Yellow or Mustard Yellow. Small addition of Charcoal Grey deepens it.
- Navy — Dark Blue + small amount of Charcoal Grey.
- Warm grey — Charcoal Grey + small amount of Barn Red or Squash Orange. Produces a greige tone rather than a cool grey.
- Teal — Turquoise + small addition of Dark Green. Shifts the blue-green toward a deeper teal.
- Burnt orange — Squash Orange + small amount of Barn Red.
- Always mix dry pigments first before adding to your concrete mix — blending dry produces more even results than adding colours separately to a wet mix.
Practical Tips for Working With Iron Oxide Powders
Iron oxide powders are fine and will temporarily stain skin, work surfaces, and clothing. Wear gloves when measuring and mixing. Work on a covered surface. The staining on skin washes away easily — it is the work surface and clothing that are more permanent.
Store pigments in sealed containers away from moisture. Although iron oxides are chemically stable, clumping from humidity makes accurate measurement harder and can cause uneven colour distribution in your mix. A dry, sealed container keeps them in working condition indefinitely.
Always measure by weight rather than volume for consistent results between batches. A teaspoon of pigment varies significantly in actual weight depending on how densely the powder has settled. A small kitchen scale accurate to 0.1g is the right tool for weighing pigment against your cement quantities.
Iron Oxide Pigments — Available in Jamaica
Twelve colours, concrete grade. Sold individually. Available islandwide and ships to USA and Canada.
Shop Pigments