Thanks for that Charles. Straight away by looking at the ring (annulus) and the stem (stipe) I can tell it's not a Cortinarius. The name Cortinarius comes from the 'cortina' or web-like structure that extends from the edge of the cap (pileus) to the stipe in the immature fungus thus protecting the young gills (lamellae). As the pileus expands this annulus is left in the form, usually, of a fine webby structure adhering to the stipe. As the Cortinarius species have rusty brown spores as they mature you will see these caught on that remnant on the stipe often just as a rusty coloured line rather than any robust structure. On a closer look the colour I'm seeing on the lamellae is only on the edge of the lamellae and looks like it is the result of drying out and ageing. When I look down into the lamellae they look white. I suspect that this is a Macrolepiota/Chlorophyllum. A number of the Macrolepiota have been moved over to Chlorophyllum. My gut feeling is that it may have been a Macrolepiota dolichaula!! Sorry I can't be any more precise.