Millrind

A millrind or simply rind is an iron support, usually four-armed or cross-shaped, for the upper ("runner") stone in a pair of millstones.

The rind is affixed to the top of the square-section main shaft or spindle and supports the entire weight of the runner stone, which can be as much as several tons. The face of a runner stone usually has a carved depression, called the "Spanish cross", to accommodate the millrind. The rind is necessary because the grain is fed through the runner stone's central hole, so the spindle cannot be inserted through it like a cartwheel on an axle.