This dark red sandstone and maroon siltstone, interbedded with shale, can be seen along the Belle Fourche River.

Siltstone is a fine-grained sedimentary rock with many of the same properties as shale.

The Goldenville group consists of a sequence of siltstones and sandstones approximately 6.7 km thick.

Colluvial Fines: silt, clay, and fine sand; derived from substrate weakly consolidated shale and siltstone substrate

Ponderosa Pine on dark red sandstone and maroon siltstone, interbedded with shale (not visible), along the Belle Fourche River.

Thus, sandstone, siltstone and shale are interrelated rocks that are distinguished by particle size.

The group comprises sandstones with limestones and dolomites and some mudstone and lesser amounts of siltstone.

Siltstone and shale, two types of sedimentary rock called clastic rock, form from "clasts" -- that is, fragments of other rocks or minerals.

Siltstone commonly occurs adjacent to sandstone deposits -- that is, near beaches and delta edges where sand is deposited.

Carved into solid siltstone, each grotto descends around 30 meters underground and contains stone rooms, bridges, gutters, and pools.

The world oldest dildo is a siltstone 20cm phallus out dated 30,000 years of age present in a cave in Indonesia.

The Victoria Goldfields are hosted in Cambro-Ordovician sand and siltstones as are the Eastern Goldfield of Nova Scotia.

On one pair of siltstone tablets, I notice some unusually large, deep and scary-looking footprints, each with five arched toe marks, like nails.

Carved into solid siltstone, each grotto descends around 30 meters underground and contains stone rooms, bridges, gutters and pools.

Carved into solid siltstone, each grotto descends around 30 metres underground and contains stone rooms, bridges, gutters and pools.