Formed Sydney in 1922 by the amalgamation of Abermain Colleries Ltd. and Seaham Colleries Ltd. it had a red flag with a narrow black diamond or fusil bearing a white "A" fromThe Log 11/1987. In 1931 it merged into J & A Brown & Abermain Seaham Colleries Ltd.
Began by James and Alexander Brown, brothers and owners of the Minmi Mine (Richmond Main and Pelaw Main) Newcastle New South Wales transhipping coal to Sydney. James, the more active within the partnership, took on the Australian Agricultural Society who enjoyed a monopoly on the coal distribution in a 'limited' mining for maximum sale price situation. After several attempts, James won thus, enabled greater allowable tonnage of coal to be mined and enabling the demand to be met, especially at a time when the California Gold Rushes and their need for coal for industry there saw Newcastle Australia as the nearest available source as well as having high quality coal in itself.
Red flag with a large upright black diamond, centered on the cloth and its tips touching the top and bottom edges, charged with a white upper case "A".
A black diamond ("◊") is a usual symbol of coal mining and related activities.