Unusual Vase with mystery marks

[bardicprose]

I recently purchased this old vase at a yard sale. It is marked J.F Co Dutch Silver on the bottom. I suspect the "Dutch" part refers more to the style/content of the vase or perhaps the alloy of silver used. I cannot find any reference to a JF Co. The vase itself looks like it might have been painted at some point?(there is a thick white coating in the recesses, with hints of other color in places) the whole thing is heavily patinized. I think it's a repousse piece. On the bottom around the mark you can make out some reds spots. I thought this might be rust at first, but I looked at it under a loupe and it looks more like blobs of paint.

Any ideas on the age/maker/alloy?