Riche vs. fortuné
While both riche and fortuné translate to rich or wealthy, they are not always interchangeable. The main differences lie in their scope of use, level of formality, and connotation.
Riche
A2Riche is the most common and versatile word for rich. It can be used literally to describe a person's financial status, but also figuratively to describe things that are abundant in quality, content, or components.
Il est assez riche pour acheter cette maison.
(He is rich enough to buy this house.)
Ce gâteau au chocolat est très riche.
(This chocolate cake is very rich (in fat and sugar).)
La France a une histoire riche et complexe.
(France has a rich and complex history.)
Cette région possède un sol riche, parfait pour l'agriculture.
(This region has rich soil, perfect for agriculture.)
C'est une langue riche en expressions idiomatiques.
(It is a language rich in idiomatic expressions.)
Le musée propose une riche collection d'art moderne.
(The museum offers a rich collection of modern art.)
Fortuné
B2Fortuné is a more formal, elegant, and somewhat literary term. It is used almost exclusively to describe people of great financial wealth and often implies a certain social standing or inherited money. It is not used for food, soil, or experiences.
Elle vient d'une famille fortunée de banquiers.
(She comes from a wealthy family of bankers.)
Seuls les collectionneurs les plus fortunés peuvent acquérir de telles œuvres.
(Only the wealthiest collectors can acquire such works.)
Il a mené la vie d'un héritier fortuné.
(He led the life of a wealthy heir.)
Le quartier est habité par des gens d'affaires fortunés.
(The neighborhood is inhabited by wealthy business people.)
Un généreux et fortuné mécène a financé le projet.
(A generous and wealthy patron funded the project.)
Summary
In essence, riche is the general-purpose word for rich and can be applied to people, food, history, soil, and more. Fortuné is a more sophisticated term reserved specifically for financially wealthy individuals or families, often used in formal or literary contexts. You can describe a meal or an experience as riche, but never as fortuné.