Why Genuine Stones
A lot of "birthstone" jewellery isn't what it sounds like.
Scroll through Instagram and you'll see dozens of "birthstone necklaces" being sold by well-known brands. Often, what you're actually buying is cubic zirconia — coloured glass, not the real stone — with the truth buried deep in the product specs, if it's mentioned at all.
At Rainbow Rocks, we tell you exactly what you're buying. Every piece is labelled clearly — natural gemstone, lab-grown gemstone, or coloured cubic zirconia — in the title, the description, and on the product page. No hidden specs. No small print. If we've used a CZ, we call it a CZ. If the emerald is lab-grown, we say so. If the moss agate is natural, we tell you it's one-of-a-kind.
This page explains the three stone types we work with, why we're transparent about them, and why any of it matters.
What "genuine" actually means
Three terms get used interchangeably across the jewellery industry, and the difference is everything. Here's how we use them at Rainbow Rocks — and how you'll see them on every product page.
Natural gemstones are mined from the earth — like the moss agate in our Vine and Willow collections, the peridot in our Mira ring, or the black onyx in our Layla hoops. Each one is unique because it formed over millions of years. No two are identical, which is part of what makes them special. On the product page, you'll see "natural" in the title and description.
Lab-grown gemstones — our lab rubies, lab emeralds, lab sapphires — are real gemstones grown in controlled environments from the exact same chemical composition as mined stones. They're physically, optically, and chemically identical to their natural counterparts. The difference is they're more affordable, ethically sourced, and free from the environmental cost of mining. A lab emerald is still an emerald — just grown above ground instead of underneath it. On the product page, you'll see "lab" or "lab-grown" in the title.
Both natural and lab-grown stones are genuine gemstones. When we use the word "genuine" on Rainbow Rocks, that's what we mean — the real material, in either form.
Cubic zirconia (CZ) is a different stone material altogether. It's a synthetic simulant — a lab-created stone that looks brilliant, sparkles beautifully, and is designed to resemble diamond or coloured gemstones at a fraction of the price. CZ has its place: some of our most-loved designs are offered in a CZ version for customers who want the aesthetic at a more accessible entry point. But CZ isn't an emerald, a ruby, or a peridot — it's CZ, and when we use it, we call it CZ. In the title. In the description. In the metafields.
If a piece in our catalogue says "genuine peridot" or "natural moss agate," that's what it is. If it says "CZ" or "cubic zirconia," you're buying CZ. No sleight of hand, no surprises when it arrives.
The vermeil difference
There are several common ways to put gold on jewellery, and most high-street brands don't tell you which one they've used. The thickness of the gold matters — but what's underneath the gold matters just as much.
| Type | Gold layer | What's underneath |
|---|---|---|
| Gold plated | A very thin gold layer (usually 0.25 microns) | Brass, copper, or steel — a base metal that can turn skin green once the thin plating wears through |
| Gold filled | A thicker gold layer | Still a base metal core — usually brass or copper. The outer gold lasts longer, but the piece isn't precious throughout. It can't be polished, resized, or reworked without exposing the base metal underneath |
| PVD gold plated stainless steel (select chunky designs only) |
A durable vapor-bonded gold coating — more scratch-resistant than standard plating | Surgical-grade stainless steel — hypoallergenic, inert, and tarnish-resistant. Not a precious metal, but a deliberate choice for heavy chunky pieces where solid sterling would be prohibitively expensive and uncomfortable to wear. Clearly labelled on every product |
| Vermeil (our main range) | A minimum 2.5-micron layer of real 14K gold — ten times thicker than standard plating | Solid 925 sterling silver — a precious metal. Vermeil is the only "plated" category where both the outer layer and the core are precious metals |
| Solid gold | 9K, 14K, or 18K gold throughout | The same gold, all the way through |
The overwhelming majority of our pieces are true vermeil: a thick layer of real 14K gold bonded to a core of solid 925 sterling silver — precious metal on top of precious metal. We don't work with brass or copper as a base because when those wear through, your skin pays the price. Vermeil lasts for years with proper care, and because there's no base metal hiding underneath, it's hypoallergenic and suitable for sensitive skin.
Why our gemstone pieces aren't made in stainless steel
You may notice other brands offering "gold" gemstone jewellery at similar prices in stainless steel. There's a reason we don't. Stainless steel is extremely hard — much harder than gold or silver — and that hardness makes it structurally unsuitable for properly setting gemstones. Professional jewellers and metallurgists agree: the metal is too rigid to flex prongs around a stone without risking damage to the stone, and the intricate detail work our designs require (pavé accents, halo settings, prong details on delicate rings) simply isn't possible in stainless.
So what do the brands that use stainless steel with stones do instead? Most resort to glue. The stones are bonded to the setting with epoxy rather than properly prong- or bezel-set by a jeweller. In the short term, it looks fine. In the medium term, the glue weakens, the stones loosen, and — per countless customer reviews on Amazon, Overstock and elsewhere — stones fall out within months. At that point, repair means returning the piece to the manufacturer, or often, throwing it away.
We take gemstone setting seriously. Every stone in every Rainbow Rocks ring, necklace and earring is set by a jeweller using traditional prong, bezel or pavé techniques into sterling silver or 14K gold. Not glued. This is why our main range uses vermeil over sterling silver: the metal is the right hardness to be worked into a secure, beautifully detailed setting that holds for years.
Where PVD stainless fits in
For a small range of chunky statement designs — where stones aren't the focus and intricate setting isn't required — we use PVD gold-plated surgical stainless steel. This is a deliberate choice for that specific use case: chunky pieces in solid sterling silver would be heavy, expensive, and uncomfortable to wear. PVD stainless steel is tarnish-resistant, hypoallergenic, and one of the most durable finishes in jewellery — better than most "gold-plated" pieces on the high street. It isn't a precious metal core like vermeil, but every piece that uses it is clearly labelled "PVD stainless steel" on the product page. You'll never buy it thinking it's something else.
If you're not buying solid gold (which most people aren't, at these price points), vermeil is the option where what's inside the piece is as real as what's on the outside — and for chunky pieces where precious-throughout isn't practical, we've picked the next-best durable, honest alternative.
Nickel-free, hypoallergenic
Sterling silver and solid gold are naturally hypoallergenic. Because our vermeil pieces are 14K gold bonded to sterling silver — not brass — they're suitable for sensitive skin. Our PVD stainless steel pieces use surgical-grade stainless, the same material used in medical implants — also nickel-free and hypoallergenic. Across every piece in our range, you won't find brass or nickel on skin.
If you've worn fashion jewellery and ended up with green stains on your fingers or irritated earlobes, that's usually nickel or brass in the base metal. Not here.
Why any of this matters
You can buy a "gemstone" ring for £15 on fast-fashion sites. It'll sparkle beautifully in the Instagram photo. It'll tarnish in six weeks.
You can buy a lab emerald ring from Rainbow Rocks for £83 in 14K gold vermeil over sterling silver. It'll still look the same in two years, and it'll mean something to the person wearing it. That difference — in what you're actually putting on your skin, in what it costs the planet, in what you're left with at the end — is the whole reason this brand exists.
Explore the collection
Every piece in our range lists its exact stone origin, metal base, and finish on the product page. If it doesn't, we haven't made it.
