Blue Chattered (?) Bottle Vase mark GB LM

Hi Folks,

Found this in a charity shop in France ... but I have a feeling its English.

Very well executed cobalt glaze on stoneware. Vague 'chatter' lines near the neck.

8"/20cm tall. 2.75"/7cm diameter.

The mark looks like GB then L or C M on the base.

It has been used for pouring oil ... that could possibly mean that a stopper is missing (unless it was a cork stopper).

Could it be Gordon Baldwin? (Just kidding!) But any ideas will be appreciated. Thanks.