The tiny pieces of metal in your phones are much more valuable than you think.

"Each phone contains about 300 mg of silver and 30 mg of gold. Just the gold and silver used to manufacture the phones sold this year are worth more than $2.5 billion," scientist Hywel Jones, from England's Sheffield Hallam University, says in his report "Dialing Back On Cell Phone Waste."

Jones' research also shows that in 2014 more than 1.8 billion new cell phones will be purchased, and almost half of them (44 percent) will be collecting dust in a drawer in a few years when the consumer moves on to a new device.

Only 4 percent of old cell phones are being recycled.

Currently, the systems used to recycle electronics are not saving the maximum amount of reusable materials. The person who takes the reusable materials out of an electronic device are usually subjected to breathing in toxic fumes, reports Chemical and Engineering News.  

Some experts are brainstorming ways to make recycling old phones more practical. Ideas currently being thrown around in the industry include motherboards that can dissolve to make precious metals easily recoverable, starting to use cellulosic materials for the phone's skeleton and circuit boards and using electroplating to recover the metals, reports News Every Day.