Monty E. writes: I seem to remember the dollar symbol $ with two bars going through it instead of one. Which is the proper use of the symbol and what countries use it on their coins?
The proper way – the single line. (Check your computer keyboard). Along with the United States, Mexico, Portugal, the British Virgin Islands and Hong Kong use the dollar symbol. Note: some countries that use “$” only use this symbol on coins.
The origin of the dollar symbol originates with the 16th century Portuguese “Cifrao” that was used like we use a comma in thousands. This symbol used two perpendicular strokes over an “S”. The Spanish version of this symbol was called the “calderon”. There was also a stylized “P” and “s” that represented pesos, pesetas or Spanish 8 reales.
The Portuguese used the symbol “$” but with two lines in the same way as we use the comma as a separator when we write a number in thousands. For example: 1,000 would have been written 1$000.
By the late 18th century, correspondence expressing accounts in pesos or Spanish 8 Reales show that the peso symbol had melded with the calderon. When there is a conversion to dollars both the single line and double line “S” appear to be interchangeable (the U.S. dollar = 1 Spanish 8 Reales). The U.S. dollar is currently usually expressed as an “S” with one perpendicular line but note that Mexican Pesos are still expressed with the old peso symbol with two perpendicular lines.
Also note that U.S. and Mexico never use the “$” symbol on their respective currencies, probably because the symbol is ambiguous.