metamorphic

Rounded gray pebble, likely fine-grained metamorphic rock

Possibly quartz-rich gneiss or granofels; exact identification requires closer examination

AI-generated identification · may be incorrect

Pale gray, fine-grained, rounded and water-worn, with dark mineral flecks and a thin dark seam. Likely hardness around 6–7 if quartz-rich; no obvious crystal faces or cleavage are visible.

Identified October 3, 2026More metamorphic →

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Physical properties

Pale gray, fine-grained, rounded and water-worn, with dark mineral flecks and a thin dark seam. Likely hardness around 6–7 if quartz-rich; no obvious crystal faces or cleavage are visible.

Formation & geological history

A rock fragment likely weathered from a larger outcrop and rounded by transport in a stream or along a shore. If metamorphic, its minerals recrystallized under heat and pressure; its age cannot be determined from the image.

Uses & applications

Primarily a beach or stream pebble and a collecting specimen; similar durable rocks may be used as aggregate or decorative stone.

Geological facts

The dark line may be a mineral-rich seam, fracture filling, or surface mark, so it is not diagnostic on its own.

Field identification & locations

The smooth rounded shape indicates abrasion during transport. Check a fresh surface and test hardness; identifying minerals or layering would narrow the rock type and its likely source.