Age of Bronze Cast Buddha with Green Patina

Hi,
From my mother's attic I found this 7" statue of Buddha, heavy but hollow, we think it's bronze (rings like a bell when you tap it). It's got an extensive greenish copper patina. Could it get this from being exposed to moisture over the years?

I have seen other really old bronzes, which are uniformly dark brown.

I suspect it might be made in Asia for sale to tourists - If anyone has seen anything similar before, all information appreciated.

Cheers!

 

https://www.invaluable.com/auction-...ure-standing-laughing-buddha-256-c-34a4b39b96

 

https://www.ebay.co.uk/itm/38674637...k9Wnl+7rcpgF9FXYWx1qaBOg==|tkp:Bk9SR4SsrIvCZA

 

He is a depiction of the Japanese God of happiness and contentment, Hotei (Chinese Budai) -
https://www.onmarkproductions.com/html/hotei.shtml

Here is another one, being offered on Australian ebay for AU $230 -

https://www.ebay.com.au/itm/1163209...QiKLpXOba50BKPbHxyO+Aftg==|tkp:Bk9SR_al1ZXCZA

The fact that we have found several essentially identical statues indicates that they are not unique, but were produced in some quantity. The surface appears to be an applied patination (a treatment created at the time the statue was made), rather than the result of a natural corrosion process due to age.