4 Dollars

The Westmorland Bank of New Brunswick was a short-lived chartered institution operating out of the Bend of Petitcodiac — the town later renamed Moncton in 1855. A 4-dollar denomination is characteristically North American; British colonial banking culture in the Maritime provinces inherited the awkward overlap of sterling and dollar reckoning, and four-dollar notes answered a specific computational need when converting between the two systems at the common rate of £1 = $4.

The bank itself failed in 1867, and surviving notes were never redeemed at full face value. That financial collapse, combined with the low print runs typical of provincial Maritime banks, keeps genuine examples genuinely scarce.