Sculpting of a dissolvable body by flowing water

Fluid flows strongly influence the dissolution of materials in geological contexts and in chemical and pharmaceutical applications. We approach flow-driven dissolution as a moving boundary problem and conduct experiments on hard candy bodies immersed within fast flowing water. We discover that different initial shapes are sculpted into a similar final form before ultimately vanishing, suggesting convergence to a stable shape-flow state. A model linking the flow and solute concentration suggests an explanation for this state and offers scaling laws for quantities such as the volume decay rate in time. As a whimsical application, we also show how this model can be used to address the long-standing question, ``How many licks does it take to get to the center of lollipop?''