W. Kerr was a Sydney-based jeweller, according to Carlisle. His work included medals, trophies, cups and mounted eggs. In 1879 he made a cricket trophy (now held by the Powerhouse Museum); in 1888 he made a Fire Brigade prize medal and regalia for the Royal Antediluvian Order of Buffaloes in silver and gold (Powerhouse Museum). In 1892 he was awarded a medal by the Agricultural Society of NSW for his silver mounted emu eggs (Powerhouse Museum).
In the twentieth century his work included an eight hour day badge (1905), a silver two-handled trophy cup engraved with an image of harvesting wheat (by William Kerr [Junior], Powerhouse Museum), a cricket shield presented by Samuel Hordern to the Centennial Park Cricket Association (1914) (Powerhouse Museum) and medals from Mexican silver dollars recovered from the Emden cruiser which had been sunk by HMAS Sydney (1914 - NU 20937-8).
AMOL website http://amol.org.au/collection/collections_index.asp.
Carlisle, L. (1983). Australian Commemorative Medals and Medalets from 1788, p.130.