Plaque reads:
[Crest of Australia]
This plaque was unveiled by The Right Honourable Malcolm Fraser, C.H., M.P., Prime Minister on 12 November, 1981
To commemorate the start of building construction of the new Parliament House'
As a bonus underneath the plaque itself carved in the marble it reads:
' Her Majesty Queen Elizabeth II opened this building for The Commonwealth of Australia on 9 May 1988'
submitted by: @IanThorp