Definitely not A.gemmata which is more straw coloured, usually has white veil remains on cap surface and never has such an obvious volval remain in the ground surrounding the stem base.
Although the stipe looks pale, this is most probably A.crocea - the colour on the inside of the stipe membrane is the same colour as the cap.
This is Amanita excelsa, the bulbous base of the stem enclosed in the universal veil remains (not shown) would tell me it is an Amanita and the grey remains on the grey to olive-brown cap tell me what species.
All Amanita gills in Britain are white/ish so an underview would tell me nothing more.
I must add that I am not sure what Project Noah hope to achieve as there are so many misidentifications here that when people google a species and a wrong one is shown, then possibly a whole new generation could be viewing a misnamed species.