We’re used to seeing gold locked in vaults or sparkling in jewellery, but one of the most valuable roles it may soon play is completely invisible.
Around the world, scientists and security specialists are exploring how gold nanoparticles can help fight the war against counterfeiting — with potential applications in everything from product packaging and pharmaceuticals to high-security documents. It’s a 21st-century solution from one of Earth’s oldest and most trusted materials.
Luxury goods like handbags are a growing target for counterfeiters — gold-based security tech could help ensure what’s real stays real.
From fine wines to honey exports, gold-infused authentication labels could protect Australian producers from imitation and fraud.
Gold’s Role in Anti-Counterfeiting Technologies
In Australia, this emerging use of gold is attracting growing interest, particularly as industries seek new ways to guarantee authenticity in an increasingly complex global marketplace. From premium food exports and fine wines to pharmaceuticals and branded packaging, Australian researchers and businesses are exploring how gold’s optical properties at the nanoscale could help verify the real thing — and weed out the fakes.
While not yet in use, gold nanoparticles may one day enhance the security of Australian passports with invisible, tamper-proof markers.
At RMIT University in Melbourne, a team of researchers has developed a type of gold-based ink that changes colour depending on how it’s viewed. This is thanks to a phenomenon known as surface plasmon resonance — the way gold nanoparticles interact with light at different angles.
These nano-enabled inks could be printed onto labels or packaging to create unique visual signatures that are incredibly difficult to replicate. While still in development, the technology holds strong potential for sectors where provenance and product trust are paramount, such as Australian wine, honey, and designer fashion.
The CSIRO has also explored the use of gold and other nanomaterials in secure labelling, hoping to develop next-generation traceability technologies. These systems could embed microscopic markers into coatings or packaging, which could then be scanned at different points in the supply chain. In high-risk areas like pharmaceuticals, agriculture, or defence logistics, such technologies offer a potential way to trace and verify a product's journey — with gold offering a uniquely stable and tamper-resistant platform for this kind of embedded data.
A future use case for this technology may be in Australian passports or banknotes - an idea which is gaining traction in research circles. Australia has a long-standing reputation for innovation in secure document design — from pioneering polymer banknotes to developing features like transparent windows, microtext, and ultraviolet imagery. The same characteristics that make gold nanoparticles so effective in packaging and product authentication — their stability, light-reflecting behaviour, and invisibility to the naked eye — could one day enhance the next generation of high-security Australian identity and currency documents.
Why gold?
What makes gold especially attractive for these technologies is its chemical stability. It doesn’t rust, tarnish, or degrade — even at the nanoscale — which means a gold-based security marker created today could still be detectable decades into the future. And because only minute amounts of gold are needed to produce these effects, the cost can be surprisingly efficient, especially in high-value industries.
As Australia continues to position itself as a leader in premium, traceable exports and responsible gold production, gold is once again proving itself to be more than a symbol of wealth. These emerging applications hint at a future where gold’s value isn’t just measured by the ounce — but by the trust and security it quietly provides.