Amber features of Châtellerault-La Désirée. A: Several amber pieces showing a wide range of colors and shapes, some translucent grains having a thin whitish crust (arrow); B: SEM view showing the typical fracturing on the surface of an amber grain (arrow); C, D: Thin section of opaque amber grain showing intense colonization by filamentous microorganisms; E: Thin section of opaque grain showing a mixture of bullous (arrow) and colonized (arrowhead) areas; F. Thin section of opaque amber grain showing complex resin fluxes underlined by micro-sized bubbles; G: SEM view of microbubbles; G: Thin section with detail of innumerous microbubbles. Pictures by Jean-Paul and Simona Saint Martin.