Mrs Janet Anderson Thomson first proposed the idea of a Northwest Territories tartan after attending an RCMP ball in Yellowknife in 1966. Mrs Thomson enlisted the help of Hugh MacPherson, a designer in Edinburgh. She chose the colours and Hugh produced three draft designs from which this one was chosen by an official committee. The tartan was unveiled at the 48th Session of the Territorial Council in January of 1973. Green represents the forests, white the frozen Arctic Ocean, blue the Northwest Passage, gold the mineral wealth of the NWT and the red-orange, described as 'autumn colours', represents the barren lands or 'Arctic prairies.' The tartan also contains a thin black line representing the northern treeline. Note: the tartan is listed as "North West Territories" in the official register.