- cap is blue, up to 15 cm broad, convex and inrolled at the edges.
- older specimens are greyish-blue and have a depressed center.
- flesh is indigo colored, staining green when cut.
- cutting across the gills releases a dark indigo latex which turns green.
- gills are light blue and descend slightly down the stem.
- stem is indigo/blue and hollow.
- grows under conifer and hardwood stands.
- appears in late summer or fall.
- taste is mildly bitter or neutral, with no odor; cook before eating.