Stamp collecting is big business in Asia. Keith Heddle, group investment director at Stanley Gibbons, said "Our investor base in Asia is growing fast, as high net worth individuals buy stamps for investment and look at alternatives not just to mainstream options, but also to fine wine, art and most recently, gold." While Chinese rarities are appreciating in value, iconic British stamps such as the Penny Black and Two Penny Blue are constantly sought after. In fact, British stamps are the most widely collected in the world. Singapore is no stranger to acquiring expensive British stamps. An Edward VII 6d stamp overprinted with "IR Official" issued in 1904 was sold to a Singaporean investor in 2010 for £375,000. That was the rarest and most expensive single British stamp that Stanley Gibbons offered up until last year when the Plate 77 Penny Red was sold for £550,000 last year via its Hong Kong office. The most expensive item Stanley Gibbons had in stock was a reunited block of twelve 2d (Two penny) blues worth £950,000. This was sold recently to a collector in Australia. While a hobby for many, rare stamps have proved to be a valuable asset class over the long-term, acting as a useful hedge against volatile stock markets. The GB30 Index, which tracks the prices of 30 of the rarest stamps of Britain, has risen by more than 11 per cent each year for the past 10 years. However the market is fairly illiquid as stamps are rare and traded very infrequently. Last year Stanley Gibbons launched the GB250 Index to provide a broader view of the investment market for stamps from Britain.