You can't miss the huge stamp mosaic at the Counter Hall of General Post Office in central. The mosaic, which is 6.45 metres wide and 3.97 metres high, depicts the Hong Kong cityscape and is composed of used stamps donated by the staff of 98 global postal administrations. It is so big that Hongkong Post has filed an application to the Guinness Book of World Records. Philatelic Bureau senior manager Vinci Wong said the project took nearly a year to complete - six months collecting stamps and the rest of time putting the stamps on the 30 panels which make up the mosaic. Staff in different districts each completed a panel. 'We ran into trouble when black stamps were needed. Black is very special in stamps. The Singapore postal administration saved us by offering a small amount and we found the rest in our own products from 2003,' Mr Wong said. He also said that the mosaic is supposed to convey the value of Hongkong Post - linking people and delivering business. Au Yeung Kan-ho, officer in-charge of the Kowloon East Sorting Office, said helping to make the mosaic provided relief from his routine work. 'We deal with stamps every day but this was the first time I realised that stamps not only deliver our letters but also show our feelings,' said Mr Au Yeung, who thought the project was a success. 'We made it in our spare time, with our families,' said Mr Wong, who asked his Form Three son for help when he had trouble with the calculations involved in putting together the project. 'It was a very great activity for parents and children,' he said. In a move aimed at sharing the project with the public, Hongkong Post is holding a competition inviting people to guess the number of stamps used in the mosaic. Customers can collect application forms from any post office or submit an electronic entry form to the Hongkong Post website, www.hongkongpost.com . The deadline is on Thursday.