West German mid century vase

This is an intriguing little item. It is a West German pottery mid century vase with an unusual organic shape evocative of some kind of mollusc. The chocolate brown base colour is partially covered with a textured white glaze which resembles frost. It also features squiggly lines of metallic gold and more gold to the rim and base. On the base the form number 7000 can be clearly seen. There is also a number 13 which must relate to the size, as the vase measures 13 cm high at its lowest point. There is an indistinct word in gold letters, and a gold letter F. The word 'Foreign' can also be seen. We haven't been able to identify the maker - if you have any ideas, we would be grateful if you let us know!