A granite surface ground smooth and clean by a glacier.

The abrasion of bedrock surfaces by materials carried on the bottom of a glacier. This process leaves these surfaces smooth and shiny.

The smooth and shiny surfaces that are produced on rocks underneath a glacier by material carried in the base of that glacier.

is the leveling and smoothing of rock by fine-grained debris at the glacier bed. Coarser rocks may gouge scratches called striations.

Glacial polish is a characteristic of rock surfaces where glaciers have passed over bedrock, typically granite or other hard igneous or metamorphic rock. Moving ice will carry pebbles and sand grains removed from upper levels which in turn grind a smooth or groved surface upon the underlying rock. The presence of such polish indicates that the glaciation was relatively recent (in geologic time scale) or was subsequently protected by deposition, as such polish will be subsequently lost due to weathering processes (such as exfoliation).