Variations in French Indochine 1/2 Cent km#20

Hello to all,
On a recent trip to Vietnam I came across the 3 coins you can see below, all 3 are 1/2 Cent km#20.
Two of them are XF from 1938, the one in the middle is quite worn, from 1935.



Both coins from 1938 weigh 4.08 g. and 4.01 g. respectively, which is according to Numista and other coin catalogues. Instead, the one from 1935 only weighs 3.35 g. You can see in the picture as well that thickness is smaller.

Is somebody aware of variations in this coin? Or it's just fake?

Thanks for your help.

Your 1935 coin could be in Zinc but zinc coins are reported for years 1938 and 1939 (diam 21mm, weight 3g)

It looks to me that the reduction in weight could be because the coin is worn. That being said, it is a lot of weight lost because of wear and tear. I've seen coins that have only .35 grams off because they are over 150 years old, and only a little worn down and was a soft metal (silver). By this time in history (1935), making coins was much more precise, especially with bronze and copper. To me the colour of the metal also looks fine (just worn down and dirty).

I would lean on the side of it being real, and just super worn down, but I know that French-indochina coins are quite often fakes. But it looks real enough to me. (Most of the fakes are not that worn down because they will not get as high of a price)

Hope this helps:)

Some French coins during WWII were minted on planchets of different thickness, see the list below for examples. It is not documented for your type, but it can be imagined that it is a more common phenomenon for French coins.

Consider posting your question in the French forum. If you don't speak French, you could simply drop a link there to this thread to draw their attention to your question. But don't forget to apologize if you do that in English

https://en.numista.com/catalogue/pieces18131.html
https://en.numista.com/catalogue/pieces300.html

https://en.numista.com/catalogue/pieces18129.html
https://en.numista.com/catalogue/pieces708.html

https://en.numista.com/catalogue/pieces18132.html
https://en.numista.com/catalogue/pieces298.html

Hi, thanks to all for your fast answer.

I thought about the Zinc variant, but it's not documented for year 1935 and in any case is a super rare coin, so it's like if you win the lottery. Maybe someone knows an easy way to distinguish between Bronze and Zinc without damaging the coin.

The coin is wore down, but you can still see the details on both sides, so it's difficult to think that material reduction and still keeping the details.

A possibility is that this coins was minted with a thinner planchet.

Best regards to all.