Its thallus is typically immersed, but can rarely be superficial and then thin, indistinct, and dark grayish green with a granular appearance.

[1][4] The stalk is shiny black, 0.11-0.17 mm wide, and consists of blackish brown to dark aeruginose, irregularly interwoven and strongly sclerotized hyphae that become paler towards the surface.

The exciple is dark brown to aeruginose, composed of elongated to almost isodiametric sclerotized hyphae that are paler in the outer part and distinctly anticlinally arranged.

[4] Calicium glaucellum grows on old stumps, standing or fallen wood of both coniferous and deciduous trees, and more rarely on bark.

[4] Calicium glaucellum is recognized by its rather short-stalked apothecia, the presence of a white rim along the edge of the exciple, the usually immersed thallus, and the medium-sized spores with an ornamentation of irregular ridges and cracks.