Kaiyan Tongbao

Please, I have this coin and I have difficulty identifying it. The writing is of the kaiyuan tongbao, but it has 24 mm and thickness of approximately 1 mm. the reverse of it is totally smooth, without pattern.

Hello,

Without pics, hard to tell.

Welcome to Numista, by the way !

Verweis : "Choucas"​Hello,
​
​Without pics, hard to tell.
​
​Welcome to Numista, by the way !

​Indeed, very hard to tell.

Excuse me! I thought you inserted it. Here are the photos. And thank you for the reception.

my opinion: replica

Verweis : "PetrusAscanus"​my opinion: repica

​I actually think it could be real, many of these coins have been turning up after some hoards were discovered in China a few years back.

https://en.numista.com/catalogue/pieces41543.html
https://en.numista.com/catalogue/pieces131222.html

As for being a replica, I also mistrusted, but it's pretty worn out the material looks like cast bronze! Would it be a bad replica made?

Ok, can be real, but the white color (gypsum) does appear a lot on replica's

Hello,

I'd say genuine. It's a Kai yuan TB of the early type (621-718). Hartill #14.1.
That kind of patina often appear on fake ancient coins, but it can also be genuine. I also have a HuangSong TB (genuine) with a black patina and such white color on it.

Chinese cast coins offer a wide variety of patinas and color that other ancient coins don't offer. Some of them would look fake on other coins. I wonder if there is any paper about patinas and their explanations (locations, ground, alloy,...). I guess it would be interesting.