He owns several successful businesses but this company is the 'jewel in the crown'. [=this company is the most valuable/important/admired]
The guests were heavily 'jeweled'. [=the guests were wearing a lot of jewelry]
The building is regarded as one of the 'jewels' of modern architecture.
(..) Update me on the structural and compositional analysis. The scepter is alien. There are elements I can't quantify. So there's elements you can. The jewel appears to be a protective housing for something inside. Something powerful. - Like a reactor? - Like a computer. I believe I'm ciphering code. (..)2015 Avengers: Age of Ultron