Clement et Florian Berthier works the Upper Loire, where Sauvignon Blanc reaches its mineral peak. The region's chalky soils and cool climate shape wines of precision and restraint. The winery's portfolio centers on three expressions of the variety: Terre de Marne and Terre de Silex, named for their respective terroirs, alongside La Croix Renaud Sancerre Blanc. Each captures the interplay between limestone and flint that defines Upper Loire Sauvignon—bright acidity, white stone minerality, and the kind of structural clarity that rewards attention. Wine Enthusiast, Wine Spectator, Decanter, and Wine Advocate have all assessed the range, with Terre de Marne and Terre de Silex earning particular recognition among prestige critics.