5c & 10c (Nickels & Dimes?)

Dime comes from the same French word as tithe - or tenth (then disme, and then dime). This was because the US dollar (or Canadian) was originally subdivided into a decimal system, so it made sense.

And nickel comes from the metal composition of the original base metal 5c.

Now for Aussie coins, it used to use the LSD system (Pounds, shillings, pence). During D Day (decimalization), 10 shillings (1/2 pound) was worth one new dollar, 5 shillings to the 50 cent... so each shilling was worth 10 new cents. In fact, the current sizes of the 10, 20c are the same size of the old legacy shilling, florin from Australia (and UK and NZ because they were pegged to each other).

So not trying to be an expert - but I would think if there were a legacy name for the 10c, 20c, it would be shilling/bob and florin/two bob

The terms nickel,dime,and quarter emigrated to Canada from the US.I was wondering why "nickel" and "dime" didn't cross the Pacific.

dbm -

oz was where GB shipped their criminiminals, so they were likely to use the GB terms.

Never ever!

Yer well the politicians and landowners of the time were criminals just the same, they just brought off the law.

20c ....is still 2 bob too me

In the US, "dime" is the official name of the 10 cent coin; it says so right on the coin: "ONE DIME". The name was a legacy of the attempt to introduce a truly decimal (base 10) currency in the US: 10 cents to a dime, ten dimes to a dollar, ten dollars to an eagle. The dime is the only surviving legacy of this original system, with the US dollar now a de-facto centesimal currency system (100 cents to the dollar).

In Canada, the 10 cent coin was introduced at par with the US dime back in the 1800s, and circulated side-by-side with it for many years. Combine that with the common cultural links between the US and Canada and it was only natural that a coin the same size, weight and value would acquire the same name, albeit unofficially in Canada. Australia has never seen the US dollar in widespread circulation side-by-side with our own, and apart from a brief interaction during WWII there was virtually no cultural exchange with North America. So we have no such historical or cultural links that would see the nickname transferred here.

With regard to the nickel, it is a "nickname" on both sides of the US-Canadian border. The Canadians deliberately chose specifications similar to the US 5 cent coin when they introduced their cupronickel version of the 5 cents in the 1920s. So again, a similar sized coin circulating side-by-side would inevitably acquire the same nickname in Canada, and a quite dissimilar coin would not do so in Australia.