I would recommend anyone who is interested in this technique to have a look at Marina Barovier's Carlo Scarpa, Glass of an Architect, published 1999 ISBN 88-8118-328-X.
In particular attention should be paid to the description of the 1928 Parisian Salon on p34: "an original use of opaque glass, which Scarpa employed, together with the application of gold leaf, to meet the new taste." There are further references to the " 'Phoenician' decoration, a technique which made these objects unique pieces, their quality being exalted by the strong colouring of the glass fabrics and by the application of gold leaf to the whole surface." These pieces which were produced by MVM Cappellin & C. are illustrated on pp58, 63/4 and the Phoenicians on pps66-71. In addition due regard should be paid to the images on pp72-81 and 87.
Alternatively, similar images of this work by Carlo Scarpa can be found in "Venetian Glass" - 20th Century Italian Glass - The Nancy Olnick and Giorgio Spanu Collection, published in 2000 by The American Craft Museum, New York, ISBN 1-890385-05-0. It is interesting to make a comparison between the Scarpa pieces shown 1929 -1936 and the piece produced by Archimede Seguso some twenty years later and entitled "Polveri"
The work to which I refer is very rare to find and I think it would be fair to assume that Mike Harris would most likely have been unaware of its existence when, together with William Walker, he began to develop Azurene, which was a hugely successful range*. In any event there is no doubt that the use of gold and silver leaf in Azurene bears his Mike's own unique "handwriting" and any suggestion that it was not original would be incorrect. However, it is not historically correct to assign to Mike the somewhat dubious accolade of being the first person to use gold and silver leaf as external decoration.
*During the mid eighties I played a small part in its success as I was running my family's gallery Coleridge, which was a major retailer for Isle of White glass from 1982 to 1986 and we bought and sold considerable volumes. Indeed, I might even have sold the piece that started this thread!