Gold Sovereigns and Why the same design and how

My family and I have been into Gold Sovereigns lately as Prices dropped. 

I have a question regarding the mint-marks, as the only way to tell them apart.

I guess I want to know why and how this came about, I mean this same design is on so many coins South Africa, UK some made in Canada.

How did all these sovereign countries/mint's agree on the same design except the mint mark?

And all over several year spans that dont necessarily cross each other. 

put in gold, 8grams, 22 mm and the word sovereign and damn!

Fairly simple really, they were all British Colonies, they were set up by the British, they ordered the dies, and they were made in London and sent to the various locations so they could mint coins using local gold. 

I wasn't aware of the existence of mint marks on sovereigns. Could you point one out please?

Kopeika

I wasn't aware of the existence of mint marks on sovereigns. Could you point one out please?

https://www.bullionbypost.com/info/sovereign-mint-marks/

Kopeika

I wasn't aware of the existence of mint marks on sovereigns. Could you point one out please?

N#115428

This one has an “M” Mintmark .. made at the Melbourne Mint in Victoria, Australia.

They also have “S” & “P” Mintmarks on Australian Sovereigns.

The only confusing part is that when you search numista some are under UK. others under their respective country. 

that's true, the colonial issues are under the modern day countries, Australia, India, South Africa or Canada. 

That's how they are to be found in Krauss as well.

the mint mark is not easy to see. the 1918 I  in particular.

I suppose Krause goes by what collectors do, and it's true that, for example, Canadian collectors tend to collect “C”-mintmarked sovereigns.

And yet, these are not Canadian coins; they were struck at what was then the Ottawa Branch of the Royal Mint (now the Royal Canadian Mint). I'm happy to see that Canadian Edward VII and George V sovereigns are listed under the UK in the Numista catalogue. But others should be listed here as well. The portrait used in both cases is bare headed; the crowned portrait was always used in this period on coins of the colonies, including the more autonomous dominions.

However, the Canadian sovereigns are listed as non-circulating while the UK ones are assumed to be circulating and this is certainly a mistake. I think they were all circulating, even though of course they weren't meant for buying a loaf of bread or a pair of socks.

Whoa, that answers a lot, but also confirms my point, a bit confusing. I got it now, but still is amazing for this much coordination to happen within a regime. Man most countries cant even agree on what goes on the obverse, of anything, LOL. I find it extreme OCD for that day and time.

Looks like the discrepancies and inconsistencies aren't limited to what's mentioned above. Looking at the two sovereigns linked,

Edward VII shows    W=7.99g, D=22mm, T=1mm

while George V has W=7.99g, D=22mm, T=1.5mm

One of those has to be wrong. This is entirely unacceptable! (╯°□°)╯︵ ┻━┻

Here is a search in the catalogue for all sovereigns from George IV (1821…) to George VI (…1952):

Sovereigns 1821-1952 

It is possible that some of these coins were meant to be used in the colonies where they were struck, but I suspect most were actually struck and immediately “exported” to the United Kingdom.

The only British colony that is known to have had its own gold coinage is, somewhat surprisingly, Newfoundland. 

Here are the ones I got

1927 South Africa / has SA mark below horse right rear hoof

1931 South Africa / has SA mark below horse right rear hoof

1912 UK -  no mint mark, so I assume UK?

1915 UK - no mint mark

bee yoo tee full 😁

correct - no mint mark = uk

All Georges, you need an Eddy and a Vicky

Mr. Midnight

All Georges, you need an Eddy and a Vicky

What about a Lizzy?

true, that. 

I have a 1958

and I just got my Vicky