MELBOURNE, Australia — Quarter Carat was founded on one principle: that people deserve to know exactly what they are buying.
That principle shapes everything we do — from how we engineer our alloy, to how we stamp every finished piece, to how we describe our product in every ad, caption, and product listing. This article sets out the Australian standards that govern gold jewellery, where 6K sits within and outside those standards, and why we choose to be explicit about all of it.
The Australian Standard for Gold Jewellery
The principal technical standard governing gold jewellery in Australia is AS 2140, published by Standards Australia. It specifies composition and marking requirements for jewellery made from precious metals.
AS 2140 is a voluntary standard, not a mandatory law. But it operates alongside the Competition and Consumer Act 2010 (Cth) and the Australian Consumer Law, which prohibit false or misleading representations about the composition of goods. Together, these set the framework for how gold jewellery can be described and sold in Australia.
Under AS 2140, the recognised fineness marks for gold jewellery are:
- 375 — 9 karat (37.5% pure gold)
- 585 — 14 karat (58.5% pure gold)
- 750 — 18 karat (75.0% pure gold)
- 916 — 22 karat (91.6% pure gold)
9K at 37.5% pure gold is the minimum fineness that AS 2140 recognises for gold jewellery. Pieces at or above this threshold can be described and marketed as gold jewellery under the standard.
Where 6K Sits
6K gold contains 25% pure gold. It sits below the AS 2140 minimum fineness mark of 375 (9K).
That means Quarter Carat cannot and does not describe its pieces as gold jewellery in the sense defined by AS 2140. We describe them accurately: as pieces made with 6K solid gold alloy, containing 25% pure gold. Every product listing and every article on this site states the gold content clearly and specifically.
This is not a workaround. It is the correct description of what our product is: a solid gold alloy with 25% pure gold content, engineered for daily wear, at an accessible price point that 9K cannot reach.
What “Solid Gold Alloy” Means
When we describe our pieces as a solid gold alloy, we mean one specific thing: the gold alloy runs all the way through the piece. There is no base metal underneath. There is no gold coating applied to a surface. The material you see on the outside is the same material throughout the band, the links, the post, the clasp.
This is the construction distinction that separates our pieces from plated, filled, or vermeil jewellery:
- Gold plated: a thin surface layer of gold over a base metal. The layer wears away.
- Gold vermeil: a gold coating over sterling silver. Still a coating. Still a base metal core.
- Gold filled: a thicker bonded gold layer over a base metal. Still a base metal core.
- 6K solid gold alloy: gold alloy throughout. No surface layer. No base metal underneath.
The material value, the wear characteristics, the absence of a reactive base metal beneath the surface — these are properties of construction, not marketing language. A 6K solid gold alloy piece does not behave like plated jewellery.
How We Back Our Claims
Making claims about metal composition is straightforward. Proving them is a different matter. We prove ours in two ways.
Every finished piece is stamped. The inside of every Quarter Carat piece carries two marks: the 6K karat mark and the QC maker’s mark. The karat mark identifies the gold content. The maker’s mark identifies us as the responsible party. These are not decorative. They are a declared commitment, stamped in metal, on every piece we sell.
Every finished piece is tested. We use an XRF metal analyser — the same category of instrument used by customs authorities, refineries, and precious metal traders — to verify the elemental composition of every finished piece before it leaves production. The machine reads the exact percentage of each metal in the alloy. Our results: gold, silver, copper, zinc. No nickel. No cadmium. No reactive metals. The composition matches what we stamp. Every time.
This is not industry standard practice. Most jewellery brands do not test finished pieces at this level. We do it because our position — introducing a karat that Australian consumers have not encountered before — carries a responsibility to be verifiable, not just credible.
Why We Created 6K
The gap between fashion jewellery and fine jewellery has been widening for years. Fashion jewellery is plated, affordable, and disposable. Fine jewellery is solid gold at 9K and above, meaningful, and increasingly out of reach as gold prices rise.
6K exists in that gap. It is not a lesser version of 9K. It is a different answer to a different question: how do you give someone access to a solid gold alloy — real gold content, no coating, no reactive base metal — at a price point that 9K cannot reach?
The answer is 25% pure gold, engineered with purpose, in a proprietary alloy blend of gold, silver, copper and zinc.
A Note on Transparency
We state the gold content on every product: 25% pure gold. We name the alloy metals: gold, silver, copper, zinc. We disclose the absence of nickel and cadmium. We stamp every piece. We test every piece.
We do this because transparency is not a marketing position for us. It is the only reasonable approach for a brand introducing a new karat into a market that has never seen it. Consumers deserve to know what they are buying. We have designed our entire product description and labelling practice around making that as clear as possible.
If you have a question about our alloy, our testing process, our stamping practice, or how we describe our product, we welcome it. Contact us at admin@quartercarat.com.au.
About Quarter Carat
Quarter Carat is Australia’s first 6K solid gold alloy jewellery label, founded in 2025 and built on over 35 years of combined fine jewellery industry experience. Shop at quartercarat.com.au.
Frequently Asked Questions
Is 6K gold legal to sell in Australia?
Yes. There is no law in Australia that prohibits the sale of gold alloy below 9K. The Australian Standard AS 2140 sets 9K as the minimum fineness for pieces to be described and marked as gold jewellery under that standard. 6K sits below this threshold, which is why Quarter Carat describes its pieces as a 6K solid gold alloy rather than gold jewellery. The Australian Consumer Law prohibits false or misleading representations about composition. Quarter Carat’s description of its alloy — 25% pure gold, stated on every product — is accurate and verifiable.
Why does Quarter Carat describe its pieces as a solid gold alloy rather than gold jewellery?
Because that is the accurate description. Under Australian Standard AS 2140, the minimum recognised fineness for gold jewellery is 9K (37.5% pure gold). Quarter Carat’s 6K alloy contains 25% pure gold, which sits below that threshold. Describing our pieces as gold jewellery in the same sense as 9K or 18K would be imprecise. Describing them as a 6K solid gold alloy — which is what they are — is accurate. We choose precision over a simpler claim.
What does “solid gold alloy” mean in practice?
It means the gold alloy runs all the way through the piece. There is no base metal underneath and no gold coating applied to a surface. This is the construction characteristic that distinguishes 6K solid gold alloy from plated, vermeil, or gold-filled jewellery, all of which have a non-gold metal at their core. The solid alloy construction means there is nothing to wear away to, which is why our pieces behave differently to plated jewellery over time.
How does Quarter Carat verify its gold content claims?
Every finished piece is tested using an XRF metal analyser before it leaves production. XRF (X-ray fluorescence) analysis reads the elemental composition of a metal, identifying the percentage of each element present. Our results confirm: gold, silver, copper, zinc — at the stated proportions — with no nickel or cadmium. Every piece is also stamped with the 6K karat mark and the QC maker’s mark, making the composition declaration visible and permanent on the piece itself.
What is Australian Standard AS 2140?
AS 2140 is the voluntary technical standard published by Standards Australia that governs the composition and marking of precious metal jewellery sold in Australia. It establishes recognised fineness marks for gold (375, 585, 750, 916), silver, platinum and palladium. It is voluntary rather than mandatory, but operates alongside the Australian Consumer Law, which prohibits misleading representations about product composition. Quarter Carat complies with the Australian Consumer Law by describing its product accurately: a 6K solid gold alloy containing 25% pure gold.