Small ceramic abstract sculpture with cobalt glaze

I lost my small ceramic abstract sculpture yesterday around 3pm outside the Tate Modern on Bankside in London. It's about 20 cm tall, glazed cobalt blue with tiny white speckles, and there's a barely visible crack along the rim. The piece is handmade and signed on the base with the initials 'AL'. It was a gift from my grandmother, so it feels sentimental to me and I really need it back.