What Is 18K Gold-Plated Jewelry? (And Why It Matters)
The Onyxelle Team
You see "18K gold-plated" on the label. What does that actually mean? And how does it compare to solid gold?
The basics: gold-plated vs. solid gold
Solid gold means the entire piece is made of gold alloy. A 14K gold necklace is 58.3% pure gold by mass; 18K is 75%; 24K is 99.9%.
Gold-plated means a thin layer of gold electroplated or deposited onto a different metal core. The core gives the piece its strength and shape; the plating gives it the look and feel of solid gold.
Why 18K matters
The number refers to the karat of the gold used in the plating itself.
- 10K — 41.7% gold. Yellower, harder, less premium look.
- 14K — 58.3% gold. Standard for fine jewelry.
- 18K — 75% gold. Rich color, premium feel.
- 24K — 99.9% gold. Too soft for daily wear.
18K is the sweet spot: rich enough to look luxurious, hard enough to last under daily wear. Onyxelle uses 18K because it captures the look of fine jewelry without the brittleness of pure gold.
The core matters as much as the plating
Cheap gold-plating uses brass, copper, or alloys containing nickel as the core. When the plating wears through, the core oxidizes — that's the green skin and tarnish people complain about.
Onyxelle uses surgical-grade 316L stainless steel as the core. It's:
- Hypoallergenic (nickel-free, lead-free, cadmium-free)
- Tarnish-resistant on its own
- Hard enough to survive daily wear
- The same grade used in medical implants
The plating technique matters most
Standard electroplating: a quick dip in a gold bath. Maybe 0.25-0.5 microns of plating. Wears through in weeks.
Onyxelle uses PVD (Physical Vapor Deposition): under vacuum, gold is vaporized and bonded to the steel core at the molecular level. 2-3 microns thick. The same technique used by luxury watchmakers for cases that survive decades.
What you should ask before buying
- What karat is the plating? (18K is premium)
- What's the core material? (316L stainless steel = best)
- What plating method? (PVD > standard electroplating)
- What's the warranty? (60-day minimum)
- Is it hypoallergenic? (look for nickel-free certification)
Why this matters for you
The right gold-plated jewelry should last for years. Onyxelle is engineered for it — 18K PVD gold-plated on 316L surgical steel. Tarnish-resistant. Hypoallergenic. 60-day money-back if anything goes wrong.