Oldfield received an OBE in 1990 for dressing the Queen Consort for various ceremonies over a decade.
Camilla's pale turquoise lace gown by Oldfield for her 2013 Sri Lanka tour was praised.
As a touching tribute, Camilla will wear Queen Mary's crown at the Coronation in May.
She plans to remove the contentious Koh-i-Noor diamond, which many other countries, including India, claim as their own.
Charles must wear a military uniform instead of britches and silk stockings, breaking centuries of tradition.