Just as silicon chips pack more and more function into less and less space, other electronic components have also shrunk. Tiny surface mount resistors replace the wire-ended components of just a few years ago.

Capacitors used to be bulky items - even the low voltage types. But like resistors, they too have shrunk to minuscule proportions.

Few people realise that the key to making some of these very tiny capacitors is found deep underground in Western Australia. It is the rare mineral tantalite, a complex oxide of iron, manganese and tantalum, and the principal source of tantalum metal.

Two mines in the state supply more than a quarter of the world's annual tantalum requirements. One is outside the small town of Greenbushes, 250km south of Perth. The other is at Wodgina in the remote Pilbara region, 1500km north of Perth.

Australian gold mining company Sons of Gwalia owns both and together they form the world's largest known tantalum resource. Fifty eight million kilograms of tantalum (as tantalum pentoxide) has been found, enough to give both mines at least 25 years more life.

The tantalum bearing ore is mined from huge open pits by drilling and blasting. Every tonne mined requires the removal of nearly seven tonnes of waste rock.