Embroidered burse
St Augustine's Church, Kilburn, London NW6
In ecclesiastical terms, a burse is for carrying the "corporal" — the linen cloth used to cover the elements in the Eucharist (OED)
The delicate white embroidery is perfect here: like all forms of embroidery, white on white was rather fashionable at this time, but required a great deal of skill. [Commentary continues below. Mouse over the text for links.]
Photographs by John Salmon, with thanks to St Augustine's Church; text by Jacqueline Banerjee.