In 1985 Warhol embarked on his largest portfolio of screenprints. Entitled `Reigning Queens? it contains sixteen prints of the four ruling queens at that time in the world: Queen Elizabeth II of the United Kingdom, Queen Beatrix of the Netherlands, Queen Ntombi Twala of Swaziland and Queen Margrethe II of Denmark ? the last of whom features in this poster. Based on official or media photographs, Warhol has incorporated abstract blocks of colour that, although screenprinted, appear collaged. He has also combined printed elements derived from drawings, which emphasise details such as jewellery. A Royal edition of the portfolio was published that incorporated diamond dust. The by-product of the manufacture of industrial-grade diamonds, this dust gave the prints a sparkly, extravagant effect.