Possible Clues:

• Evening gown fabric, perhaps
• Silk fabric
• Thin material turned fat, horribly fat, with infusion of energy
• In Wales a flower and in France a fabric
• Lifted plump cheese to find crisp material
• Gown material
• Party dress material
• Fabric that's very loud in a Tate sort of way
• Material of Welsh separatists?
• Silk had meal, fine and rich, sent up