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.
(..) I know all about your secret source. And I know something you don't. I know who he is. He's Karla. 'One of you has been giving Polyakov the crown jewels.' - I did not know. - Are you still a wanted man, Toby? - Look, George, I didn't know. I... - You pick ed the wrong side. (..)2011 Tinker Tailor Soldier Spy