NEW YORK (MainStreet) Think twice before you cast aside loose change along with pocket lint: that seemingly insignificant legal tender could be worth a fortune.

But complete serendipity as happened to a California couple earlier this year is not a requirement for finding hidden treasure. Auction platforms -- many of which, like Stack's Bowers Galleries, are online -- allow collectors to seek out their own pieces with ease.

And investors are doing so in droves.

The fervor in the rare coin and currency market is indeed highlighted by last year's world-record-breaking sale of the highest value coin ever a 1794 "Flowing Hair" silver dollar for a stratospheric $10 million.

That's part of a more widely-observed phenomenon: the non-profit Professional Numismatists Guild recently reported that the roaring U.S. coin was worth $5 billion in 2013.

Amid drops in the precious metals market and a buoyant stock market, investors are looking toward secure and appreciable collectibles, with a growing interest in coins coinciding with the all-time-high art auction sales of late, including the Francis Bacon triptych that fetched $142.4 million at Christie's last year.

Still, coin-collecting or numismatics as it's known to enthusiasts offers many advantages for investors, especially those without the deepest pockets.

Easy Entry

"There's so much fervor around coin collecting in today's economy, because it's so accessible to so many different people," said Vicken Yegparian, vice president of numismatics at Stack's Bowers Galleries.

For first-time buyers, there's an entry point for everyone. A Buffalo Nickel, for example, can run the gamut from $50 to a couple thousand dollars. It's an accessible and potentially lucrative hobby.

"If someone wants to collect a silver dollar from 1878, they could buy one for $100," said David Bowers, a renowned numismatist and former co-chairman of Stack's Bowers. "It's very egalitarian. You can work in a factory and build a collection, or work in Silicon Valley and have zillion dollars and have a nice collection. "

Appraising the Prize

Knowing which attributes to target can go a long way toward building a smart coin collection. Yet though nuance and details are seemingly endless in the field, the learning curve is not too steep. Collectors simply need to keep in mind the following when considering a coin:

Quality or condition

Rarity

History

Uncirculated or like-new coins are going to be worth more than those that have been knocked around. But historical significance as with the $10 million silver dollar, believed to be struck from the first U.S. mint can inflate a coin's value all the more.

Enthusiasts can also add value to their coin trove in marshaling all the coins in a particular series the 50 State Quarters Program, as a recent example to add worth as a cohesive unit.

"Our collectors are very, very passionate about collecting, their collection history and these items and objects and their connection to history," said Brian Kendrella, president of Stack's Bowers. "Our collectors love the search and the thrill of completing their collection."

Advantages of the Investment

Coin collecting also offers several advantages over investing in other collectibles.

First, these aren't one-offs.

"We're talking about objects that were oftentimes created by governments in quantity, so there's a certain regularity that allows for consistency in grading them, in valuing them," Yegparian said.

The Numismatic Certification Institute (NCI) has a clear system for appraising a coin's condition, and more checks and balances come from the Professional Coin Grading Service and the Sheldon rarity scale to determine a coin's authenticity and rarity.

To boot, coins can offer more security than straight commodities, prone to fluctuations. They have an intrinsic value, but also one attached to their history.

"We've heard a lot about gold and gold prices in the news and in the market place," Yegparian said. "Although gold is down in prices relative to the high of a few years ago, interest in rare gold coins has not abated."

Compared to other collectibles, coins are easy to store and care for. Unlike wine or art, you don't have to worry about the exposure of coins to heat or humidity. Unlike automobiles, they're portable.

The primary impetus to collect coins should be enjoyment, but the secondary benefit is that coins do often see a rise in value as has been the case, especially in the last 10 to 15 years.

"I think it is one reason why people enter coin collecting and coin investing is to diversify one's investment portfolio," Yegparian said. "It's a way to sock money into something that is relatively liquid."

That liquidity is advantageous for people who want to be able to exchange in their rare coins for actual money.

"If you pay $100,000, you could get 90,000 tomorrow if you have buyer's remorse," said Bowers. "If they bought a $100,000 watch, good luck."

There's also a convenience to it.

"People can sit in Singapore, or Hong Kong, or Zurich or Topeka and enter an online auction," Bowers said. "You can sit in your most comfortable chair. This brings many players. The market for coins is international. If you sell an Ancient Greek coin, the market is as strong in Shanghai as it is in New York City."

Plus, the future worth of these coins is secure.

"I think there will always be collectors of our financial history," Yegparian said. "I think humans by nature are collectors."

How to Dive In

Bowers recommends baby steps.

"Buy inexpensive things," he said. "Read about them. Jump in. Just build a collection. Time takes care of the collection. A nice collection put together ten years ago can be sold at a profit with commission."

But, as with any investment, don't be too whimsical.

"What they need to avoid, is buying something on impulse, saying 'we can put it into this...like a penny stock.'" Bowers said.

Make sure you're buying through a legitimate platform; go through a source approved by the Professional Numismatics Guild.

"There are an awful lot of boiler shops, telemarketers, airline magazine, the vault has just been openedavoid that," Bowers said.

Numismatics is a common ground where the Main Street hobbyist with a jones for security and a Wall Street investor eager for growth can see eye to eye.

"When you build a collection, it's like buying an index fund," Bowers said. "Don't get all hundred-thousand-dollar coins. Some should be $300 dollars. It's about balancing your portfolio."

--Written by Ross Kenneth Urken for MainStreet