What's That Rock?Slate
A fine-grained metamorphic rock that splits into smooth flat sheets. It forms from shale or mudstone.
How to identify Slate
- Splits into thin, flat, smooth slabs
- Dull, fine-grained
- Makes a dull 'clink' sound when tapped
Often confused with
Is Slate valuable?
Common.
What changes the price
- Common rock: low value as a specimen
- Roofing and tile slate is priced by area and grade
- Writing slates and décor are cheap
Uses
- Roofing, flooring, blackboards
Care
Safe to wash.
Identifying a stone from a description or a photo is an estimate. Many stones look alike. Ask an expert or a gem lab before you buy, sell or rely on an identification.
Updated October 2026