The stone is a Northern Song Emperor Huizong's Heavenly Daoshan Duan ink stone and will go under the hammer on 13th June. This might leave bidders wondering why the piece comes with such a high estimate. This is because the making of ink stones, the palette on which artists grind and mix inks before applying them to paper or silk, reached its epitome during the Northern Song Dynasty (960-1170 A.D.) with the Emperor Song Huizong at its forefront. Contemporary Chinese artists still use ink stone stones in the making of ink for calligraphy and the art from is currently as popular as ever.

The stone has deep purple-brown colour and has a underside relief of a tortoise carrying a tablet. On the recessed base are the words "By Imperial Decree: Xuan He." The estimate is $850 000-$1.5 million, although it is more likely to reach the top end of the estimate.

The sale also features a collection of historic and contemporary ink scroll paintings, including works by blue-chip Chinese masters like Zhang Daqian (1899-1983), creator of the double panel "Lotus" which has an estimate of $100 000-$150 000.

"Plum Blossoms", a 14th century Yuan Dynasty work by Wang Mian is a rare example of a court artist breaking from tradition to create an imaginative work that foreshows the boldness and vigour of later movements. The pieces is inscribed and signed with the artist seal and one colophon by Ji Tong, the painting has eight Emperors' seals and eight Collectors seals.

Check out the sale here.