I hope that you can help me with this unusual Peziza species to me, which I narrowed down to Pachyrella celtica, assumed this was renamed. The find was unusual also as not only in the UK, few records, but found under a single healthy English Elm tree in ancient woodkand. Growing sessile to the ground/soil, not on an ex-burn site, the following details decribe the species:

Body undulating, Hymenium smooth purple/brown, with outer surface bright pale lavender/grey inrolled, - note in young state in photo as no spores evident. Culutured for three wks  in back garden in flower pot! using the same base soil and checked again. Size: 20mm, clustered but separate when found.
Ascospores: (after 3 wks) 15.55 - 19.26 µm x 7.86 - 8.75 µm, verrocose warting in Cotton Blue only, repeated in Plaque Blue which showed additional two oil drops seemingly 100% of the time.
Paras/Asci: slightly longer paraphyses with asci at 194 - 272µm x 10.98 - 12.70 µm.

With many thanks Tony