The Iberian Pyrite Belt (IPD) is one of the most significant addresses for volcanogenic massive sulphide deposits and is home to the famous Riotinto copper mine, the foundation asset of mining giant Rio Tinto in the 1800s.
Mining in the belt, which runs for about 230km from Seville in Spain to Lisbon in Portugal, dates back thousands of years to Roman times.
MATSA currently comprises three underground mines, Aguas Tenidas, Magdalena and Sotiel, but underinvestment in exploration is driving Sandfire’s belief that there are more deposits to be found.
While $1.7 billion has been invested in MATSA’s infrastructure since 2005, only about $100 million has been spent on exploration during that same period – or about $6-7 million per year – though it did result in the game-changing discovery of Magdalena in 2014.
Most of that drilling work under previous owners Trafigura and Mubadala was focused on near-mine exploration to replace reserves.
“There was never really that push to add to resources and reserves,” MATSA executive director Rob Scargill said during a site visit last week.
But Sandfire believes it will be operating in the belt for many decades to come given its view of the upside.
“The resources may not support it today but that’s the belief,” Scargill said.
Current resources stand at 147.2 million tonnes at 1.4% copper, 3% zinc, 1% lead and 39.6 grams per tonne silver for 2.1Mt of contained copper, 4.4Mt of zinc, 1.5Mt of lead and 187.6 million ounces of silver, while reserves stand at 37.1Mt.
The current mine life of MATSA is 12 years but reserves have been successfully replaced since production began in 2009.
“These deposits grow and grow and grow,” Sandfire head of exploration Richard Holmes said.
“You get camps and these camps are quite amazing.”
As well as the 53.3sq.km of exploitation concessions covering the three mines, the MATSA acquisition also included about 1256sq.km of exploration concessions in Spain and 993sq.km in Portugal, as well as 467sq.km pending approval.
Holmes said that gave the company a third of the belt.
“If anyone’s seen our efforts in Botswana, we’re not going to stop at a third,” he said.
Sandfire will spend about $8 million on exploration at MATSA this financial year, which Holmes said was sufficient in the early phase of work.
The challenge for Sandfire is refining the huge amount of exploration targets.
