The purple/lilac colour of cap, gills and stipe and the thick widely spaced gills are distinctive in wet weather; it dries to a pale lilac or buff colour. 

When dry it can be very similar to the common Deceiver, Laccaria laccata

It is found in both coniferous and deciduous woodland, often with Beech.

Late Summer to early Winter.

Common and widespread in Britain.

Common in Leicestershire and Rutland.

https://www.first-nature.com/fungi/laccaria-amethystina.php