Among the cultured elite, art has been the most widely watched and talked about collectible in recent years. But it's the good old automobile that has been a better investment.
According to the Knight Frank Wealth Report, classic cars were the top performing collectible investment in 2014, posting gains of 16 percent. That narrowly beat art, with 15 percent gains, and coins, with 13 percent gains. But cars left stamps, jewelry, wine, colored diamonds and watches in the dust.
Cars have also held the pole position over the longer term. They have posted the best 10-year performance—with gains of 487 percent—as well as the best over five years, with 140 percent.
Still, prices for vintage Ferraris, Porsches, Mercedes and Bugattis aren't likely to maintain their speed. The 16 percent gain marks a big slowdown from their 47 percent gain in 2013.
"The market is returning to normal," said Dietrich Hatlapa, founder of Historic Automobile Group International, a collectible car index and advisory firm.
While Ferrari had the top sale of the year—the 1962 250 GTO Berlinetta that sold at auction for $38 million, including fees—Porsches, Lamborghini Countachs and other more "affordable" models gained more in price in percentage terms.
Art, by contrast, saw an acceleration, as the top trophy works fetched big prices at auction. Art prices in 2013 fell by 3 percent, so the 15 percent gain in 2014 marks a big shift.
Still, Knight Frank warns that while many of the rich are turning to collectibles and secure and growing stores of value, the markets for art, wine cars and other assets can be highly volatile. They can also be illiquid when everyone is trying to sell at the same time.
For now, however, the collectibles boom continues to rage on.