Geologist Gareth Joseph has used the hand-held X-Ray to analyse samples
Hand-held X-ray equipment is being used to detect minerals beneath former tin workings in Cornwall.
South Crofty mine, near Pool, closed in 1998, but owner Western United Mines (WUM) is working to reopen it.
Geologists are using the hand-held XRF (X-ray Fluorescence) device on rock samples to detect up to 25 elements.
WUM said it planned to mine copper, zinc, silver gold and other minerals, including indium, based on mineral analysis and use of the XRF's scans.
The machine works by using an intense beam of X-rays on rock samples, which make the different elements within the sample fluoresce at different rates.
The machine then reads the different wavelengths of fluorescence instantly, analysing them to provide a clear idea of the elements within the sample and in what concentration they occur.
WUM admitted it looked like a hairdryer, but added it could do in seconds what conventional scientific methods and analysis could take up to a week to prove and it was "delighted" with the results so far.
Chief Operations Officer John Webster: "We always believed there were vast mineral resources in Cornwall but this machine is proving they are potentially world class."
He added: "We have never intended to extract just tin from this mine.
"This will be a polymetallic operation which means we will also be mining copper, zinc, silver and possibly even some gold.
"We have also discovered significant amounts of indium, which is widely used in modern technology and enhances the value of our polymetallic ores significantly."
Indium is used to coat computer and TV screens.
The firm, which is investing more than £60m in the site, expects to re-open the mine in the next 12 to 18 months.
As well as tin, WUM has found copper, zinc, silver, gold, lithium, cadmium and indium which is used to coat computer and TV screens.
The company expects to be mining at the site for about 80 years.