Zhongguo Chao Cai pottery?

[James3891]

Hi all, just starting to learn about some of the meanings of different marks in pottery and first task I've taken on is trying to identify the mark on what i believe is a vase/plant pot of Chinese origin.

I've searched all over and the closest I've found is a mark on the Gotheborg site that is from the 1970's called Zhongguo Chao Cai that has the same wavy border design on the items that is around the mark.
Can't find anything else with that border.
However the internal markings are totally different so i wondered if they could be from a certain factory still but a different year or if the mark was common in that part of China.

It's quite generic and probably mass produced but really interested in it's origin as it's my grandfather's who can't remember where it came from except he's had it as long as he can remember.
It'd be nice if it was something he picked up much longer ago in his Royal Navy days but i imagine it will have been from a slightly less glamorous car boot sale in recent decades :).

Any help appreciated with this even if it's just confirmed it is a Chinese mark and not Japanese or from somewhere else.