



BIAB Gel
Deep indigo-blue named for South Australia’s legendary opal fields. Intense builder gel for absolute professional authority.
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Coober Depth – 40 – Professional Biab builder gel – 15ml
Deep, mysterious, and drawn from the underground opal fields of South Australia’s legendary Coober Pedy, this is an electric indigo-blue with profound saturation and presence. Named for the vast subterranean chambers where opals form over millions of years, Coober Depth captures that sense of hidden richness and timeless beauty. The builder gel formula creates structural integrity while delivering a colour so intense it seems to hold light within itself.
This is the shade for those who work in depths others cannot fathom. Wear Coober Depth when you need colour that commands respect without speaking—in boardrooms, creative studios, formal events, or any moment demanding absolute professional authority. The BIAB structure ensures flawless longevity while the creamy application eliminates doubt. Your nails become part of your professional signature.
Skin Tones: Dramatically striking on all skin tones; creates luminous contrast on fair complexions; deepens beautifully on darker skin; universally sophisticated.
Best Worn For: Executive meetings, formal dinners, gallery openings, creative direction, luxury brand events, professional photography
Pairs With: Yarra Valley (No. 34), Coober Pedy Shimmer (No. 42)
How To Use
Start with clean, dry nails. Remove any existing gel, polish, or product completely using an appropriate remover.
Removes natural oils, dust, and any moisture — all of which cause lifting. Then apply nail bond or primer if needed.
Apply a thin, even layer of OPAL Gel Base Coat over the entire nail. Cure immediately under your LED lamp.
Using the OPAL Builder Gel brush, scoop a small bead, place it in the centre of the nail and allow it to self-level for 2–3 seconds before spreading. Cure under LED for 60 seconds.
Apply a second, slightly larger bead for your desired strength and length extension. Cure for 60 seconds.
Using a 100/180-grit Opal nail file, shape the free edge to your desired finish — square, oval, almond, coffin, or round. Work in one direction to prevent cracking.
If applying gel polish colour, apply a thin, even first coat and cure for 60 seconds. Follow with a second coat for full opacity and cure again.
Apply OPAL Gel Top Coat in a smooth, even layer over the entire nail surface. Cap the free edge to seal the product and prevent tip wear. Cure for 60 seconds.
Pro Tip
Allow each bead to self-level for 2–3 seconds before spreading. Work in thin, controlled layers — it’s easier to add thickness than to remove it. Always cap the free edge with your top coat to prevent tip wear.
New to gel nails?
Free step-by-step video tutorials for beginners.
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The Opal difference
Developed with Australian nail technicians. Chip-free, high-pigment wear for 3–4 weeks.
Free from formaldehyde, toluene, and DBP. Kind to your nails and kind to the planet.
Each 15ml bottle gives you 25+ manicures. Salon results at a fraction of the price.
Step-by-step tutorials included. Most beginners achieve salon results on their first try.
Common Questions
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