The Bolivian government hopes to extract residual silver from the ore.

The tank leaching method is commonly used to extract gold and silver from ore.

The patio process had been used to extract silver from ore since its invention in 1557.

Around the same time, Potosí's rich surface deposits became depleted, which meant that even more labor would be required to extract silver.

In the Pacific region is extracted gold, silver and platinum.

This mill was probably used to extract gold and silver.

The patio process was a process used to extract silver from ore.

In 1824 he discovered a method of extracting silver without the need for mercury which was purchased by several American mining companies.

Miners made about $3 a day extracting gold, silver, copper or tungsten.

They found the metal did not react with acid and was unaffected by the usual process for extracting silver from lead.