Avoiding Bloom, Silicone Spots & Getting Perfect Pearlescent Effects

Master Metallics: Avoiding Bloom, Silicone Spots & Getting Perfect Pearlescent Effects

Some of the most interesting effects to make in resin art are metallics and pearlscents. A swirl of glowing gold, a flash of iridescent blue or a slight shift towards pearly can make a project appear simple to a show-stopper.

However, metallics are associated with a number of difficulties: bloom, silicone spots, streaky finishes, or pigments sinking in the pour. And when you could not get that perfect pearlscent finish, you are not the only ones.

This guide goes into the more advanced pigment techniques, including the interference pigments as well as the metallic bloom control and provides you with the troubleshooting equipment to achieve the always perfect results.

1. Understanding Metallic Pigments

Platelet-like, reflective mineral-coated (titanium dioxide or iron oxide) metallic pigments (such as mica powders or liquid dispersions) are called platelet-shaped.

• Metallic pigments → provide solid shimmer (e.g., gold, silver, copper).
• Pearlescent colours → intense use of colour depth as well as chatoyancy (effect of shifting).
• Interference pigments → colour alteration depending on the angle of light (blue-purple, green-gold).

These pigments have a different behaviour due to their shape and density when compared to a regular resin dye. To learn them is to know how to manage their floating, settling or dispersal.

2. What is Metallic Bloom?

Bloom occurs when the metallic pigments diffuse out of control on the surface of the resin creating hazy halos rather than sharp lines.

• Excess saturation of pigment.
• Resin is too thin (low viscosity causes migration of pigments).
• Heat gun/torch (overheats the paint, pushes the paint out).

• Follow the suggested ratio (normally 2-4 percent pigment by weight).
• Use a resin that is a little thicker or wait 10-15 minutes after mixing and then pour out.
• Apply gentle heat only for bubbles, not for moving pigment.

Pro Tip: For clean cells or lacing, apply metallics in controlled ribbons instead of flooding.

3. Silicone Spots & Fish Eyes

If you have seen little circular craters or bare spots where pigment refuses to stick, you’ve run into silicone contamination.

• Mixing cups or tools with residue (silicone mould release, oils, sprays).
• Pigments pre-blended in silicone carriers.
• Skin oils from handling surfaces.

• Always clean substrates with isopropyl alcohol before pouring.
• Avoid cheap pigment pastes that contain silicone.
• If spots appear mid-pour, you can drop a tiny amount of clear resin into the crater to fill it.

4. Working with Interference Pigments

Interference pigments are some of the most magical — appearing white in the jar, but revealing colour shifts when applied thinly over dark bases.

• Use a dark background (black, navy, or deep green) for maximum colour shift.
• Mix lightly into resin (too much turns it chalky).
• Apply in thin surface layers rather than flooding; interference shines most at the surface.

Example: A thin interference blue layer over black resin creates a deep, holographic blue-purple sheen.

5. Advanced Pouring Techniques

• Pour metallics into narrow channels then drag with a stick or spatula to create flowing effects.
• Avoid over-mixing; metallics can quickly turn muddy.

• Brush mica powder directly into a silicone mould before pouring resin.
• The pigment bonds to the resin surface, leaving a crisp metallic finish on the final piece.

• Build depth by pouring clear resin layers with metallic swirls suspended between.
• This prevents pigments from sinking and creates a 3D effect.

6. Troubleshooting Common Issues

Cause: Resin too thin or pour too deep.

Fix: Use a thicker casting resin or pour in layers.

Cause: Poor mixing or moisture in powders.

Fix: Pre-disperse powders in a small cup of resin before adding to the main batch.

Cause: Too much pigment blocking light reflection.

Fix: Reduce pigment load and pour thinner layers.

Cause: Pigments settling during cure.

Fix: Swirl gently 20-30 minutes after pouring to re-suspend without introducing bubbles.

7. Safety Notes

Things to do:

• Always wear gloves and a respirator when working with powdered pigments. Fine mica dust is a lung irritant.
• Work in a well-ventilated area.
• Store pigments sealed, away from moisture.

8. Choosing Quality Pigments

Not all pigments are equal. For professional results:

• Look for cosmetic-grade mica powders (ultra-fine, safe for art).
• Choose pigments specifically labelled for epoxy compatibility.
• Invest in interference and duo-chrome pigments for advanced effects.

Cheap craft powders often contain fillers that can cause clouding or weak colour payoff.

9. Quick Reference: Metallic Mastery Checklist

• Use 2-4% pigment by weight (avoid oversaturation).
• Pre-mix powders in a little resin before adding.
• Pour over dark bases for interference pigments.
• Avoid silicone contamination at all costs.
• Work in layers to prevent sinking.
• Use controlled ribbons or dusting for crisp effects.
• Always seal and polish finished surfaces for lasting gloss.

10. Conclusion

Resin art can be taken to the next level with metallics and interference pigments but they need to be practised and controlled. With proper pigment ratios, prevention of contamination, and practice with layering effects, you can get the pearlescent looks consistently without disturbances of the bloom or blemishes.

The secret isn't just in the pigment, it's in how you pour, layer, and finish it. Master that, and your resin art will shimmer like never before.