"Like any commodity, when the market is saturated with them, their value declines," Jason Haber, an agent at Warburg Realty in Manhattan, told Warren. "If under every rock you found a diamond, diamonds would decline in value. That's what is happening right now."
While the rich are getting richer and have more money to spend, she said, experiences are replacing luxury goods as a status symbol: "Where wealth used to be something the affluent wore proudly, today the wealthy are retreating into their cocoons, living behind walls and going increasingly inconspicuous."
It's part of the rise in discreet wealth, in which showing off wealth is no longer the preferred way to signify having money. Investing in education and health rather than luxury handbags and cars helps the rich gain — and maintain — access to what the middle class cannot.
The jewelry industry is increasingly dependent on millennials, who just aren't as interested in diamonds as their parents were, reported Ray A. Smith for The Wall Street Journal. To appeal to this cohort, luxury brands like Bulgari are offering edgier jewelry lines at lower price points.
The first two quarters of 2019 saw art auction sales drop for the first time in years, reported Robert Frank for CNBC. Over the past year, Sotheby's sales and Christie's auction sales decreased by 10% and 22% respectively, he wrote.
According to Artsy, the art market has shrunk over the past decade when adjusting for inflation. A 2017 article by Artwork Archive reported that mid-market prices between $10,000 and $50,000 saw an increase in sales, while artworks over $1 million saw a decrease.
Several art dealers told Rachel Corbett of Art Net last year that attendance is down in art galleries. Dealers expect gallery sales to continue to drop in the future more than any other sector, she wrote, citing TEFAF's 2017 market report. They expect deals to be more likely to occur at art fairs.
Wealthy people also appear to be spending less on art compared to other luxury items, Doug Woodham, managing partner of Art Fiduciary Advisors in New York, told Abby Schultz of Penta.
Spending on luxury cars may be booming, but spending is down when it comes to classic cars, Frank reported. Less than 50% of cars listed for $1 million sold at the Pebble Beach car auction — but those priced for less than $75,000 sold much more quickly, he wrote.
Classic car auctions in 2018 and 2019 saw a sell-through rate for cars priced at more than $1 million decrease by 20% compared to the year prior — the lowest since 2008, when Hagerty began tracking such statistics, reported Rob Sass for The New York Times.
The wealthy could be disinterested in the offerings or they could be feeling a change in the market, Brian Rabold, vice president for valuation at Hagerty, told Sass.
There are a few factors worth considering, according to Sass: Baby boomers are leaving the market and millennials aren't interested in buying or are priced out of the market, and there are general concerns about an economic downturn.