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.
(..) Yes. Precisely. It only works if all the little cogs mesh together. Now, a clock needs to be cleaned, well-lubricated and wound tight. The best clocks have jewel movements, cogs that fit, that cooperate by design. I'm being metaphorical, Bob. Know what I mean by cooperative cogs? Bob? (..)2004 The Incredibles