Left stone radical — a pictograph of a rock dropping from a cliff (top-left slope) with the boulder below. The indexing radical, anchors
砧 in the stone-tool family:
砖 brick,
矿 ore,
砸 to smash,
碎 broken,
磨 grind. Marks
砧 as a stone object — a flat block used as an anvil or chopping board, the rock you strike or cut against.