"Only a few years ago the mobile phone was a brick-like, unreliable and expensive device targeted at the few with deep, reinforced pockets. "Today, it's a small, light, everyday, inexpensive product used by more than 700 million people, or about 12 percent of the world's population.
"What led to this dramatic change?
"One important factor was the use of certain metals, such as copper, nickel, palladium, gold and tantalum, to help reduce the size of a cellular phone.
"Industry experts say that all the technology now packed into a mobile phone, such as batteries, flash memory chips, microprocessors and LCDs (liquid crystal displays), could have filled a whole office floor less than 30 years ago.
"Take for example the silver-gray precious metal tantalum, which is largely mined in Australia and Central Africa.
"Tantalum, a powder compacted for use in producing passive capacitors, has been a key factor in reducing the size of the mobile phone in recent years