|Heraldry of the World
Civic Heraldry of Belgium - Belgische Gemeentewapens / Armorial de Belgique
The arms were granted on September 14, 1970.
During the ancien régime, Koersel was part of the estate of Lummen, which was a jointly governed by the Prince-Bishops of Liège and the Dukes of Brabant. The arms show the chequered bar and the lion of the Counts of the Mark, as Lords of Lummen. Wilhelm of the Mark, received the estate of Lummen in the late 16th century in loan from the Prince-Bishops of Liège.
The free quarter shows the arms of the Counts of Looz, predecessors of the Counts of the Mark as Lords of Lummen.
The previous arms were granted on October 30, 1946 and had the same elements, but in a less accurate design
Literature : Servais, 1955