Help! Unusual Square Landscape Vase Signed FS? SF?

Interesting piece. The letters SF bring to mind Sheila Fournier who did a lot of interesting work when working with her husband Robert at Lacock Pottery. This reminds me of using the texture of the vase to explore the image wanted. You see a landscape. It could be a beach and waves,
or desert and dunes. Its very simplicity encourages the imagination. Could not definitely say its her work, just reminds me of the sort of thing she might have done. Robert Fournier also used texture to explore the nature of the item, in his pebble vases.