Literal translations:
* Diamant exquis: This is a straightforward translation, but it might sound a bit stiff.
* Diamant extraordinaire: This is a more dramatic option, meaning "extraordinary diamond."
More nuanced translations:
* Diamant magnifique: This translates to "magnificent diamond" and emphasizes beauty.
* Diamant somptueux: This means "sumptuous diamond" and implies luxury and richness.
* Diamant précieux: This translates to "precious diamond" and highlights its value.
The best translation depends on the context and the specific meaning you want to communicate.