Don't throw your half of the bill away - it's worth $10. The Bank of Canada in Ottawa says damaged Canadian paper money - even bills which are burned in a fire - can be worth all or part of their face value depending on how bad the damage is.

Torn bills are worth full value if three-fifths of the note remains intact. If between two-fifths and three-fifths is intact, the bill is worth half its value and if you have less than two-fifths of the bill, it's worth nothing.

Bank of Canada officials determine how much a damaged bill is worth by placing it on a piece of plastic the same size as the bill. The plastic is divided into a grid, or series of squares, which allow the bank to accurately calculate how much of the note is intact.

Bills which are burned to ashes in a fire can also be worth their full face value, he said. If a stack of bills goes up in smoke the Bank of Canada has special scientific tests which can determine how many bills were burned and the denomination of each lost bill. The tests are often used when stores or other businesses lose money in fires.

So, if your Canadian bills go up in smoke, don't throw away the ashes.