The rich cobalt blue seen on the current vase is sometimes referred to as 'sacrificial blue'. This name derives from the use of vessels bearing this colour glaze during sacrifices at the Imperial Altar of Heaven. In AD 1369 the first Ming dynasty emperor Hongwu issued an edict declaring that the vessels used on the Imperial altars should henceforth be made of porcelain. Each altar was associated with a specific colour of porcelain, and in addition to blue being used on the Altar of Heaven, red was used on the Altar of the Sun, yellow on the Altar of Earth, and white on the Altar of the Moon. Compare a similar example with this cobalt blue glaze but slightly taller in size from the Nanjing Museum (62.3 cm.), included in the exhibition catalogue Qing Imperial Porcelain, Hong Kong, 1995, no. 66; and another (59.3 cm.) included in the exhibition, The Wonders of the Potters Palette, Hong Kong Museum of Art, 1984, no. 85; and a third of comparable height (55.3 cm. high) from the Budo Takashiro Collection, was sold at Christies Hong Kong, 26 November 2014, lot 3275.