metamorphic

Dark rock specimen (possibly slate or shale)

Unidentified fine-grained rock; slate is foliated metamorphosed shale, while shale is sedimentary mudrock

AI-generated identification · may be incorrect

Dark gray to black, dull, and fine-grained with an irregular outline; the image does not show enough detail to confirm layering, cleavage, or mineral grains. Hardness and specific gravity cannot be reliably determined from the photo.

Identified September 23, 2026More metamorphic →

Explore Dark rock specimen (possibly slate or shale) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

If slate, it formed when shale was compressed and weakly metamorphosed; if shale, it formed from compacted mud in quiet-water settings. Age and origin cannot be established from this image.

Uses & applications

Slate is used for roofing, paving, and decorative stone; shale is used in cement and brick manufacture. This small specimen is most likely of educational or collection interest.

Geological facts

The worksheet visible behind the specimen has both metamorphic and sedimentary columns, so it does not establish the rock’s identity. A fresh broken surface and visible foliation would help distinguish slate from shale.

Field identification & locations

Inspect for thin, planar layers and splitting: slate tends to split into flat sheets, whereas shale commonly has a dull, earthy surface and may crumble. Similar dark rocks occur worldwide; a hand specimen or hardness test is needed for confident identification.