What is a Ruby Roman and why is it so expensive?

A Ruby Roman is a type of Japanese grape.

They are described as "absurdly expensive!"

These grapes are valued for their size and flavour.

They have only been on the market since 2008 and are only grown in Japan's Ishikawa Prefecture. The Ruby Roman is a cross between red grapes and large black Fujiminori grapes.

Standards for their culture have been strictly specified. Annual production is only about 20k bunches, so their rarity and quality are reasons for their price: in 2020 a single bunch sold for $12,000.

https://a-z-animals.com/blog/why-are-ruby-roman-grapes-so-absurdly-expensive-in-japan/