How is extreme luxury defined?

Supercars, diamond rings, $10,000 wine: what makes valuable things valuable?

Auction houses don’t just sell expensive items – they create and market the very definition of luxury. But what rules dictate what is, and isn’t, a luxury item?

This week, Sotheby’s auction house in New York City is kicking off a multi-sale luxury auction with a lineup that includes a BMW owned by Steve Jobs and a 2013 wine that’s estimated to fetch up to $40,000.

But what exactly is luxury? How is it even defined, and how do auction houses pick what to sell, and how much to sell it for? Why should a brooch go for tens of thousands of dollars, and why include an unusual watch with a melting, Dali-esque face?

We visited the auction house to ask the experts: what are the rules for slapping the label “luxury” on an item? Watch the video for their answers. Video by Sebastian Diaz, interviews by Bryan Lufkin. Additional production by Yinxue Liao.

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