Bog Manganese Brown-Black

Black crusts on bog stones and stream rocks are manganese — a true mineral black.

Color

Cool deep brown to violet-black

Binder

Gum arabic + honey

Black crusts on bog stones are manganese — a true mineral black you can chip off and grind.

▸Look for stones in springs and seeps with a thick velvety dark coating.
▸Chip the crust into a mortar, grind very fine, sift through cloth.
▸Cave painters were using this exact pigment 17,000 years ago.

Steps

01
Chip the dark crust off the stones with a hammer.
02
Grind the crust in a mortar to fine powder; sift through stocking.
03
Mull with water on a tile to a silky paste.
04
Stir in binder and pan up.

Materials

— Stones with a thick black-brown crust from a bog, spring, or mineral seep
— Hammer, mortar and pestle, fine sieve
— Gum arabic + honey binder

Safety

Moderate Risk

Involves dust, mild chemistry, sharp tools, or solvents. Use PPE and ventilate.

Hazards identified

Airborne dust — respiratory irritant

Quick checklist

☐Wear an N95 / FFP2 mask when handling dry powders
☐Mix in a tray to contain dust; wipe surfaces wet
☐Work in a ventilated area; keep food and drink out of the studio
☐Read each material's safety data sheet (SDS) before starting
☐Have water, soap, and a first-aid kit accessible

Heuristic guidance derived from listed materials. Always consult each material's safety data sheet (SDS) and a qualified instructor before attempting.

Notes

The same pigment used in the Lascaux cave paintings 17,000 years ago. Fully lightfast.