Antique Chinese Vase

The vase is 23cm high x approximately 11cm wide.

White/grey with a blue dragon painted on it in traditional Chinese form.

It’s surprisingly heavy for it’s size and it has a strange marking on the bottom.

I would like to know the story behind it and whether or not it is of great value as it was left for me in my grandmothers will with no explanation.

Any help is greatly appreciated, thank you.