This last set of stamps illustrates the 20th century history of ceramic tiles in Portugal.
The tiles by Barradas are part of a larger panel in the Humanities School of the University of Lisbon. The tiles by Keil are part of a street panel on Infante Santo Avenue, in Lisbon. The two other stamps depict tiles in the collection of the National Tile Museum, also in Lisbon. Cargaleiro’s tiles are an update of the 18th century single figure style shown in the third issue.
Maria Keil was one of the major forces of the revival and renovation of the art of tiles in the second half of the 20th century, having designed from 1957 to 1982 the abstract tile panels decorating 19 Lisbon subway stations. You can see her and Cargaleiro’s work, amongst others, by selecting the individual stations on the Lisbon Subway Art site.
The stamps were designed by the Post Office Philatelic Services, lithographed by the Mint on enamelled paper sheets of 5×10 stamps, with a phosphor band and perforation 12×11¾, and issued on 13 February, 19 June, 20 August and 15 November 1985, circulating until 31 December 1992.