- Name also: American Copper, Common Copper
- Family: Gossamer-winged Butterflies – Lycaenidae
- Subfamily: Coppers – Lycaeninae
- Wing span: (Very) Small, 22–32 mm (0.86–1.25 in.). Females larger than males.
- Wing upper side: Forewing shiny reddish yellow with almost four-angled black blotches, margin dark brown. Hind wing dark brown, margin shiny reddish yellow, often also with small blue blotches.
- Wing underside: Forewing orange with black blotches, margin grey–light brown. Hind wing grey–light brown with small black blotches and reddish stripe along margin.
- Habitat: Dry slopes and rocky outcrops.
- Flying time: First generation mid-May–late June, second July–August. In Lapland only in July.
- Overwintering form: Caterpillar.
- Larval foodplant: Docks, especially sheep’s sorrel (R. acetosella), common sorrel (Rumex acetosa), curled dock (R. crispus) and northern dock (R. longifolius).
The small copper is quite common in southern Finland and rare in the north. It can be differentiated from other coppers by the square-shaped blotches on the upper side of the forewings and the quite unclearly separated small spots on the underside of hind wings.
Males wait for females, defending their territory on bare hill-tops. Females lay their eggs individually on the leaves of the host plant.