50 Pounds

The Australian Bank of Commerce had a short and troubled existence — formed in 1910 through the amalgamation of the Bank of Queensland and the City of Melbourne Bank, it collapsed the same year it opened, never achieving a stable trading position. Notes of this issue almost certainly never entered general circulation; the bank's failure was swift enough that most surviving paper was either redeemed or cancelled administratively.

A 50 Pound denomination from a bank that effectively ceased operations within months of printing is an extreme rarity by any measure. No central authority was involved — this was a private commercial bank note, issued under the old system of competitive private currency that Australia was in the process of dismantling.