The London International Stamp Exhibition 1950 was an international stamp exhibition. It was held in the Great Room, Grosvenor House, Park Lane from 6-13 May 1950, under the chairmanship of Sir John Wilson

John Wilson (philatelist)

John Mitchell Harvey Wilson was a British philatelist, Keeper of the Royal Philatelic Collection from 1938 to 1969...

, Keeper of the Royal Philatelic Collection

Royal Philatelic Collection

The Royal Philatelic Collection is the postage stamp collection of the British Royal Family. It is the most comprehensive collection of items related to the philately of the United Kingdom and the British Commonwealth, with many unique pieces.- Early history :...

. A non-postal souvenir sheet was produced by Waterlow and Sons

Waterlow and Sons

The Waterlow and Sons Limited was a major worldwide engraver of currency, postage stamps, stocks and bond certificates established in 1897, in England.-Portuguese Bank Note Crisis:...

 for the event using the collotype

Collotype

Collotype is a dichromate-based photographic process invented by Alphonse Poitevin in 1856. and was used for large volume mechanical printing before the existence of cheaper offset lithography. It can produce results difficult to distinguish from metal-based photographic prints because of its...

 process. It depicted the Penny Black; Nova Scotia 1851 1/-; New South Wales 1850 1d Sydney View; Ceylon 1859 4d; Cape of Good Hope 1853 4d triangular. A souvenir cover showing St. George and the dragon was also available

Among the award winners was Harry Osborne

Harry Osborne (philatelist)

Harry Osborne MD was a British philatelist who wrote several important works on classic British stamps and signed the Roll of Distinguished Philatelists in 1954....

who won a Grand Gold Medal for his Great Britain stamps.