A pure white, immutably white Phlegmacium of Nothofagus forest, with a dry, chalk‑white cap that remains unchanged with age. A common and conspicuous species in Nothofagus forest, easily recognised by its persistent pure‑white colours.

Pileus: 30-55 mm, occasionally larger; dry, matt, not hygrophanous. Colour chalk‑white, remaining immutably white with age (a unique character among NZ white Cortinarii), though very old specimens may show slight greying or yellowing. Surface smooth, glabrous; margin long‑involute, not striate.
Lamellae: white to pale grey, becoming pale olive‑ochre at maturity. Moderately crowded; edge concolorous.
Stipe: 40-80 x 10-20 mm, clavate, sometimes with a short pointed root. Colour white, surface silky‑fibrillose with adpressed thin white girdles; base with white rhizoids.
Veil: White, fairly sparse; cortina white and copious, often leaving fibrillose zones on the stipe.
Context: White throughout; firm.
Odour/taste: Nil to faintly acidulous. Taste nil.