You might consider taking a closer look at all that loose change in your pockets, purses, wallets and sofa cushions. You see, there may be more cash in those coins than you think.

At bustling Renton Coin Shop, owner Steve Campau and his staff are literally being nickeled-and-dimed, and quartered and dollared!

Forget face value. Some of the silver coins they see are worth $7.50!

"Dimes, quarters or half dollars that were minted in 1964 or before have 90 percent silver in them," Campau said.

If you come across silver coins minted in 1964 or earlier, don't spend them. They're worth more than seven times their face value. People who've been stashing silver coins are cashing in.

But you don't have to be a collector to make a profit. Collect old foreign coins? Most have little collector's value at $2.35 per pound.

Everyday change can hold a hidden windfall. Look for coins with mistakes.

"Well, errors are special in the sense that there's not a lot of 'em," said Campau.

Be on the lookout for a 1942 silver dime with Lady Liberty on the front. And pay close attention to the 2 on the date.

If you can see a 1 under that 2, you've got a coin worth more than $500.

Keep your eyes peeled for 2004 Wisconsin quarters.

It's supposed to picture a dairy cow, wheel of cheese and a perfect ear of corn. But thousands turned out with a low-hanging corn husk leaf, and thousands more came out with the leaf even lower.

"Usually they're about $65 dollars and up," Campau said.

The prices range from $65 to more than $200.

"It's a quarter, and you can turn it into money," said said Campau.

And in a tight economy, every little bit helps.

For those of you with collections of Kennedy half dollars, those minted 1964 or earlier have 90 percent silver, remember that's more than seven times face value. Those minted from 1965 to 1970 have 40 percent silver, so they're worth more than face value, too.

But Kennedy half dollars minted after 1970 have no silver. They're only worth 50 cents, so if you have them, spend them! That's money you could be using now. 

One exception:  If you have a large quantity of post-1970 Kennedy half dollars that have never been circulated, don't spend them until you have them checked out by a reputable coin dealer.  Even though there's no silver, many collectors will pay a premium for that perfect coin.

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