Grown in just one country in the world, one bunch of these Japanese grapes can sell for $90 to $450. Ruby Roman grapes are evaluated on three qualities: their uniform color, size, and taste, all of which impact the final value. The grapes were developed by a union of local farmers and the Ishikawa government. In 2020, one bunch of these grapes sold at auction for $12,000. That's about $400 a grape. So why are these grapes so expensive?