Slate Pebble

Slate

Slate is a fine-grained, foliated, homogeneous, metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade, regional metamorphism. It is the finest-grained foliated metamorphic rock. Foliation may not correspond to the original sedimentary layering, but instead is in planes perpendicular to the direction of metamorphic compression.

Pebble

A pebble is a clast of rock with a particle size of 4–64 mm (0.16–2.52 in) based on the Udden-Wentworth scale of sedimentology. Pebbles are generally considered larger than granules and smaller than cobbles. Pebble tools are among the earliest known man-made artifacts, dating from the Palaeolithic period of human history.

Slate gray

Slate gray is a moderate shade of gray with a slight azure tinge, which represents the average color of slate, a metamorphic rock often used in stonemasonry. As a tertiary color, slate is an equal mix of purple and green pigments.

slate

Noun

1. A flake or piece of certain types of stone that tend to cleave into thin layers.

Adjective

1. Having the bluish-grey colour of slate (noun etymology 1, noun sense 4).

pebble

Noun

1. A small stone, especially one rounded by the action of water.
2. A particle from 4 to 64 mm in diameter, following the Wentworth scale.

Verb

1. To pave with pebbles.
2. To deposit water droplets on the ice.