Adele is poised to be crowned queen of the American music scene, with her album ‘21’ topping the charts for the 24th week. The singer is on course to top the American charts, marking the longest reign at number one since Prince and the Revolution’s ‘Purple Rain’ soundtrack. Experts expect the 23-year-old superstar to sell between 110,000 to 130,000 more copies by the close of play ensuring she remains at the top spot. It will be known on Wednesday if she has beaten Prince, who spent 24 weeks at the top of the charts in 1984 and 1985. A couple more weeks would see ‘21’ also become one of only eight albums to rack up six months at the top of the list. The largest-selling album in the SoundScan era is Metallica’s ‘Metallica’, released in 1991.