$285Median
15Sold (12 mo)
$1,200Last sale
Franklinite specimens for sale
21 for sale · $150–$7,500 USD
83 in the gallery
Franklinite is a zinc ferrite mineral with the formula Zn2+Fe3+2O4, typically forming dense, elongated to euhedral crystals in oxide-rich ultramafic deposits. It often displays a metallic to sub-metallic luster and a dark coloration that can range from brown to black, frequently occurring with associated minerals such as magnetite, willemite, and calcite in complex ore assemblages. Crystallographic habits include spinel-like octahedra and parting that can yield striking single crystals or small crystal groups, sometimes showing a lustrous surface when well crystallized.
- Formula
- Zn2+Fe3+2O4
- Rarity
- Rare
- Stability
- Stable
- Collector interest
- Moderate Interest
- Classification notes
- Oxide mineral; spinel-group, Zn-containing ferrite (ZnFe<sub>2</sub>O<sub>4</sub>)
Key characteristics
- Crystal system
- isometric
- Mohs hardness
- 5.5–6.5
- Specific gravity
- 5.07–5.22
- Luster
- metallic, submetallic
- Transparency
- opaque
- Color
- black
- Streak
- brown, black
- Cleavage
- none
- Fracture
- uneven, subconchoidal
- Crystal habit
- octahedral, granular, massive
- Classic / historic
Buy Franklinite specimens
View all 21Where Franklinite is found
Top localities
- Franklin22 specimens
- Franklin Mine14 specimens
- Buckwheat dump mineral collecting site11 specimens
- Sterling Hill Mine9 specimens
- Franklin Mining District6 specimens
- Germany1 specimen
About Franklinite
Notable specimens of Franklinite have been reported from classic localities in the United States and Germany, where it occurs in association with zinc and iron-rich oxides within skarn and pegmatitic zones. Collectors prize Franklinite for its historical significance in oxide mineralogy, its dense, durable crystals, and the contrast it provides when found with secondary zinc minerals. The mineral’s dark, metallic appearance pairs well with accompanying species in display specimens, making it a desirable component of specialized oxide and accessory mineral collections.
