Andrew is one of the few fully trained practitioners of this specialized art form working in the world today. He was the artist chosen to produce the Coronation Invitation for Their Majesties King Charles III and Queen Camilla. He trained intensively for three years at art school to develop the highly unique skill sets needed to produce such authentic work. With 43 years of professional experience, he brings rare knowledge, expertise and a tradition of excellence to this art form. Many of the techniques and materials he uses date back to the time of medieval scriptoriums and would be familiar to his craft ancestors.

He is a specialist in selecting calf skin vellum and preparing it for writing, painting, and illumination. An expert in applying gold leaf on gesso and other mediums, he uses recipes that have their origins in the medieval period. He is also a master at applying shell gold. He mixes to a special recipe, turning 23.5c gold powder into a fine paint, which, when burnished with agate or hematite burnishers, will "shine and reflect like a mirror."

He also uses specially prepared goose and swan quills for writing alongside broad-edged metal nibs with ground inks and other media. Occasionally, on extra special commissions, he uses egg tempera paints.

Andrew does not produce facsimiles of medieval paintings and manuscripts but rather creates original works painted and illuminated in styles reminiscent of the masters of the medieval period. He also applies the techniques to contemporary illuminated and heraldic works.