"I think people are starting to decide that they want to start dipping their feet in the water again," said rare-coin dealer Ken Smaltz, who owns K. Smaltz Inc., a company that buys and sells rare coins and precious metals. Smaltz said he's seen an increase in his business within the last several months.
"People are concerned about the economy," he said. "All of these fears cause investors to possibly seek to diversify their investment, and the type of investments they … look for in this type of environment are usually precious metals and rare coins."
The recent spike in sales of collectibles, such as rare coins, art and antiques, may reflect the increase in liquid assets the wealthy have to spend.
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"People [are] taking some of those profits derived from the equities market and the stock market and putting some of that into rare coins," said Hanlon of the Professional Numismatists Guild.
There's no question the rich have gotten richer. The average net worth of the so-called "Forbes 400," Forbes magazine's annual listing of the richest Americans, is now a record $5 billion. That's $800 million more than a year ago.
And a recent study compiled by Wealth-X, a firm that researches ultrahigh-net-worth individuals, found that the wealthiest people in each U.S. state were 19 percent richer last year than they were in 2012.
That gives rich investors more disposable income to spend on luxury items such as collectibles.