Gold is traditionally regarded as chemically uninteresting because it doesn't react readily with other substances.
But researchers at Cardiff University's School of Chemistry say when broken down into nanoparticles, containing a few hundred atoms, it becomes incredibly reactive.
That makes it an efficient catalyst to speed up chemical and biological processes.
The scientists say they have discovered gold is the best catalyst for making the main ingredient for PVC and it could replace environmentally harmful mercury.
It's hoped using gold in catalysis could mean the better use of raw materials and the ability to generate fuels, plastics and other chemicals from renewables.