$110Median
3Sold (12 mo)
$30Last sale
Arfvedsonite specimens for sale
6 for sale · $140–$1,500 USD
37 in the gallery
Arfvedsonite is a sodium-iron inosilicate that forms elongated, prismatic crystals with a glassy to sub-vitreous lustre. The mineral typically appears in deep, dark green to black hues, and often grows in fibrous or radiating habits within igneous and metamorphic rocks. Its sturdy structure and characteristic cleavage and fracture contribute to a striking, metallic sheen when facets catch the light. Where well-formed specimens occur, Arfvedsonite can present in compact clusters or as solitary prisms that emphasize its elongated habit.
- Formula
- [Na][Na2][Fe2+4Fe3+]Si8O22(OH)2
- Rarity
- Rare
- Stability
- Stable
- Collector interest
- Very High Interest
- Classification notes
- Inosilicates; Amphibole group (double-chain silicate)
Key characteristics
- Crystal system
- monoclinic
- Mohs hardness
- 5–6
- Specific gravity
- 3.3–3.5
- Luster
- vitreous, silky
- Transparency
- translucent, opaque
- Color
- black, green, blue
- Streak
- gray, green
- Cleavage
- perfect
- Fracture
- uneven, splintery
- Crystal habit
- prismatic, acicular, fibrous, radiating, granular, massive
- Classic / historic
Buy Arfvedsonite specimens
View all 6Where Arfvedsonite is found
Top localities
- Mount Malosa10 specimens
- Washington Pass5 specimens
- Mount Malosa5 specimens
- Poudrette Quarry3 specimens
- Conway1 specimen
- Mont Saint-Hilaire1 specimen
- Washington1 specimen
About Arfvedsonite
Notable specimens come from diverse localities including Malawi, the United States, Canada, Denmark, and India, where it occurs in alkaline igneous systems and pegmatites. Collectors prize Arfvedsonite for its dense, lustrous crystals and for the way its dark coloration contrasts with lighter matrix minerals. Its association with other minerals in alkaline environments often yields appealing, dramatic display pieces that photograph well and showcase classic inosilicate structure.
