Well Grown Cortinarius

This is likely Cortinarius evernuis, one of the easiest of the Corts, the largest genus of mushrooms, to identify. It has a dark purple cap which changes slightly with age. The telltale feature is the white edge on the rim and the white ring near the base of the stem. Both are remnants of a partial veil called a cortina which distinguish all Corts from other mushrooms. The rim cortina will change colour with age as well.