Believe it or not there is a subtle, yet important difference between the terms ‘Rock’ and ‘Stone’.
Though using them interchangeably is not some big faux pas, it is interesting to note they are definitionally different.
ROCK - a rock is usual replete with its natural jagged edges and mass. Rocks vary in size dramatically - from the palm of your hand to mountain sized boulders. A single continuous mass of minerals and mineraloids make up rocks. A rock is typically what we find on a hiking trail.
STONE - a stone is defined differently mostly by its shape, smoothness, and size. A stone is typically weathered by nature or human intervention till the surface has lost all protruding features. Stones can be large, but typically aren’t recognized as such when they are larger than human scale. A stone is typically what we find on the shore of a lake. Stones are used in the context of construction or decoration.
“The key thing to note is that geologists use "rock" as a broader term to describe large masses of material that make up the Earth's crust, including mountains, plateaus, and cliffs.”
Pretty cool right?