Circa 1912 100rs pale green, 200rs green, 400rs pale blue, 1000rs deep green, 2000rs yellow brown, 5000rs claret, 10,000rs deep blue, 20,000rs violet and 50,000rs yellow 'J Castilho - Estado de Rio Grande do Sul - Imposto de Sello' REVENUE issue, the set of nine fine WATERLOW COLOUR TRIALS perforated on gummed paper each stamp with 'WATERLOW & SONS LTD SPECIMEN' overprint in black or red and small hole punch. Very scarce. (Barata #34/37 & unlisted)