You'd only need an
and if you placed the adjectives away from the noun:
The letters were small and neat.
If you place them in front and use an
and, I think that places more stress on the adjective immediately after the
and.
A talented and young French actor.This almost seems to be suggesting that most talented French actors are old.
As others have said:
A talented and young actorwould be a little strange because the
and is superfluous.