Indochina 10 centimes ++ [solved]

Hello,

I had bought 6 pieces of Indochina 10 centimes and they arrived today. I tried to verify myself (I think All of these 10 centimes are FAKE), but I would like to hear some advice.

Let's start with these two pieces.



The 10 centimes pre-1920 should be .835 fineness, so I can count them as a FAKE coins?

And four remaining pieces.



Because I don't have a genuine of post-1920 silver 10 centimes coins, I try to compare to the 1903 10 centimes (.835 fineness). I see some differences but I don't know if it's OK to compare coins to a different type.

The weight of those 6 pieces are between 2.2 ~ 2.4 grams, and it's the first point to make me think they are FAKE. Could they be the error of the weight from the mint? (I don't think so. The weight loss is too much for the pieces in XF condition.)

Thanks in advance for the help.

----

I also have a non-verified Piastre, weight about 26.6 grams. I think is GENUINE but also want to hear any opinions.



Thanks again.

Regards,
Sak

The weight is the first criteria, then you might try the "ring test" or the "ice cube test"

Today, I bought a new digital scale to test these coins.

1901 - 2.32 g
1914 - 2.39 g
1921 - 2.32 g
1922 - 2.30 g
1927 - 2.39 g
1929 - 2.27 g
Piastre - 26.85 g

And after the ice test, the result is very frightening, all of them are SILVER. The ice melt instantly as it touch the coins.

They look polished.

Quote: "kolikko99"They look polished.

​I got the coins in this condition, so I don't know if someone had polished them before they come to me.

Do you think polishing could damage more than 10% of a coin's weight?

The text .680 fineness on 1901 and 1914 coins make the other four less trustworthy.

Thanks for your opinion.

Probably the seller polished worn coins?

The coins are all in grade XF (or at least, VF+). the piece 1922 and 1929 I see some scratches that make the coins lesser weight compared to other year, but in that case the coins should be much more damage that I would never buy them.

I had a conversation with the seller, point to some detail, and he told me that he thought they are FAKE too .

Thank you very much for the help and opinion.