Hübnerite
Hübnerite, Mn2+(WO4): manganese tungstate, yellowish to reddish brown with red internal reflections, hardness 4 to 4.5, density 7.12 to 7.18. Peru, Colorado.
Hübnerite is manganese tungstate, Mn2+(WO4) on the IMA list (grandfathered, 1865, USA): monoclinic, hardness 4 to 4.5, density 7.12 to 7.18, yellowish to reddish brown or black, with deep blood-red internal reflections and a yellow to reddish brown streak. Worked, it is 60.72% tungsten. It is the manganese end of the wolframite series with ferberite.
In short
- The species. The September 2026 IMA-CNMNC Master List lists hübnerite as Mn2+(WO4), status G, 1865, USA. The Handbook of Mineralogy sheet gives monoclinic P2/c, prismatic crystals striated along [001] to 15 cm, perfect {010} cleavage, hardness 4 to 4.5 (directional), density 7.12 to 7.18, transparent to translucent, streak yellow to reddish brown or greenish grey. Worked, MnWO4 is 60.72% tungsten.
- The shared-place ledger. A script over the two Distribution fields finds 7 areas named on both the hübnerite and the ferberite sheets, besides England and the USA: Cornwall, Colorado, Idaho, New Mexico, Peru, France and China. The two sheets never name the same mine or district in any of them. A place on a label does not choose the end member.
- Peru and Colorado. The sheet names “superb large crystals from the Huallapón mine, Pasto Bueno, Ancash Province”, Peru, and numerous Colorado deposits, among them the Adams mine near Silverton and Gladstone, San Juan Co., and large crystals from the Quartz Creek district, Gunnison Co. Its analysis, from the Uncompahgre district, Colorado, is 99.0% manganese of iron plus manganese, worked.
- Against ferberite. Same hardness, same {010} cleavage, same space group. The sheets differ in streak (yellow to reddish brown against brownish black to black), transparency (transparent to translucent against nearly to entirely opaque) and density: a 20.00 g piece reads 17.19 to 17.21 g in water against 17.36 g. Placing a crystal between them is on ferberite vs wolframite.
- Documented failure: hübnerite and quartz. The sheet’s association line is cassiterite, arsenopyrite, molybdenite, tourmaline, topaz, rhodochrosite and fluorite. Searched by script, the one occurrence of “Quartz” on the whole sheet is a place name, the Quartz Creek district. The sheet records no quartz associate; any quartz on a specimen is the specimen’s, not the sheet’s.
| Area | Hübnerite sheet names | Ferberite sheet names | Same named locality? |
|---|---|---|---|
| Peru | Superb large crystals from the Huallapón mine, Pasto Bueno, Ancash Province | Mundo Nuovo and Junin | No |
| Colorado, USA | Numerous deposits: Adams mine, Bonita Mountain, near Silverton; Gladstone, San Juan Co.; Sweet Home mine, Alma district, Park Co.; large crystals, Quartz Creek district, Gunnison Co. | A number of mines in the Boulder Co. tungsten district (“an ore mineral, well-crystallized”) | No |
| Cornwall, England | Wheal Gorland, Gwennap; Hingston Down quarry | Around Calstock and elsewhere in Cornwall | No |
| Idaho, USA | Blue Wing district, Lemhi Co. | Corral Creek, near Soldier Mountain, Camas Co. | No |
| New Mexico, USA | Nogal and White Oaks districts, Lincoln Co. | Elizabethtown district, Colfax Co. | No |
| France | Valcroze, Lozère; Adervielle, Hautes-Pyrénées | Chanteloube, near Limoges, Haute-Vienne | No |
| China | Duoluoshan mine, Huaiji County, Guangdong | Gejui, Hunan | No |
| Hübnerite sheet only | Nevada (Ellsworth district, Nye Co.); Arizona (Little Dragoon Mountains); Romania (Baia Sprie); Czech Republic (Horní Slavkov) | — | — |
| Ferberite sheet only | — | Spain, Portugal (Panasqueira), Germany (Saxony), California, Bolivia, Uganda, South Korea | — |
What is hübnerite? Manganese tungstate, Mn2+(WO4)
Hübnerite is Mn2+(WO4) on the September 2026 IMA list, the 2+ set as a superscript, status G, grandfathered, 1865, with the USA as the country of first description. The first reference is the Berg- und Hüttenmännische Zeitung 24 (1865), 370; the second, Minerals 12 (2022), 42. The Handbook of Mineralogy hübnerite sheet writes Mn2+WO4, says it forms a series with ferberite, and marks no type locality. Hubnerite, without the umlaut, is the same name; USGS Open-File Report 99-529, Table 1 spells it huebnerite.
What the sheet records. Monoclinic, point group 2/m, space group P2/c, a 4.8238, b 5.7504, c 4.9901 Å, β 91.18°, Z = 2. Crystals typically prismatic and striated along [001], to 15 cm; also tabular to bladed, flattened on {100}, showing {010}, {110}, {100}, {310}, {112}, {001}, {102}, {011} and many other forms; in radiating groups or in parallel. Common simple contact twins on {100}, rarely {001}; interpenetrant and lamellar twins. Cleavage perfect on {010}, partings on {100} and {102}; fracture uneven; brittle; hardness 4 to 4.5, directional.
The analysis. Uncompahgre district, Colorado: WO3 75.58, MnO 23.40, FeO 0.24, SiO2 0.62, CaO 0.13 and (Nb,Ta)2O5 0.05, total 100.02, against the ideal MnWO4 column of 76.57 and 23.43, which the script reproduces exactly. Leaving out the silica and the niobium-tantalum oxide, it recasts to 0.993 tungsten, 1.005 manganese, 0.010 iron and 0.007 calcium per four oxygens, and is 59.93% tungsten by mass. Manganese is 99.0% of the iron plus manganese, the figure also on is wolframite magnetic.
Where is hübnerite found? Peru, Colorado and the shared-place ledger
Distribution, as printed. The sheet opens: “May be an ore of tungsten at some localities.” In the USA: the Erie and Enterprize veins, Ellsworth (Mammoth) district, Nye Co., Nevada; numerous deposits in Colorado, as the Adams mine, Bonita Mountain, near Silverton, and Gladstone, San Juan Co., the Sweet Home mine, Alma district, Park Co., and large crystals from the Quartz Creek district, Gunnison Co.; the Blue Wing district, Lemhi Co., Idaho; large crystals from the Little Dragoon Mountains, Cochise Co., Arizona; the Nogal and White Oaks districts, Lincoln Co., New Mexico. In Peru, superb large crystals from the Huallapón mine, Pasto Bueno, Ancash Province. Wheal Gorland, Gwennap, and the Hingston Down quarry, Cornwall, England; Baia Sprie (Felsőbánya), Romania; Horní Slavkov (Schlaggenwald), Czech Republic; Valcroze, Lozère, and Adervielle, Hautes-Pyrénées, France; the Duoluoshan mine, Guangdong, China. The sheet does not name Devon.
The shared-place ledger. Matched by script against a fixed list of 21 place names and then read, 7 areas (not counting England and the USA) appear on both the hübnerite and ferberite sheets: Peru, Colorado, Cornwall, Idaho, New Mexico, France and China. The two sheets never name the same mine or district in any of them: Huallapón against Mundo Nuovo and Junin; San Juan, Park and Gunnison counties against the Boulder Co. tungsten district; Wheal Gorland and Hingston Down against Calstock. A label reading “Colorado” or “Cornwall” therefore says nothing about where in the series a crystal sits. Of the two sheets, only the ferberite sheet names Panasqueira.
What colour is hübnerite, and how is it told from ferberite?
Brown to red, and see-through at the edges. The sheet gives yellowish brown to reddish brown, blackish brown, black, rarely red; transparent to translucent; white to grey in reflected light with deep blood-red internal reflections; lustre metallic-adamantine towards resinous. Pleochroism is perceptible, X yellow to green or red-orange, Y yellowish brown to greenish yellow or red-orange to red, Z green or brick-red to red; biaxial (+), α 2.17 to 2.20, β 2.22, γ 2.30 to 2.32.
Against ferberite. Hardness (4 to 4.5), the perfect {010} cleavage and the space group are the same on both sheets. Ferberite is black, nearly to entirely opaque, with a brownish black to black streak, against hübnerite’s yellow to reddish brown or greenish grey streak. Density: 7.12 to 7.18 against 7.58, so a 20.00 g piece reads 17.19 to 17.21 g in water against 17.36 g. These separate the end members; the ferberite sheet says material approaching end-member composition is uncommon, and where an intermediate crystal falls is on ferberite vs wolframite.
The magnet. The hübnerite sheet prints no magnetic property; the ferberite sheet says slightly magnetic. USGS Open-File Report 99-529, Table 1 nonetheless pulled 5 huebnerite samples at 0.20 to 0.60 amp on a laboratory separator. What that does and does not show is on is wolframite magnetic.
Is hübnerite found with quartz? Its setting and associates
The setting. The sheet calls hübnerite typical of high-temperature hydrothermal vein deposits and pneumatolytically altered granites yielding greisen, and of granite pegmatites, also in alluvial and eluvial deposits. Its associates are cassiterite, arsenopyrite, molybdenite, tourmaline, topaz, rhodochrosite and fluorite. Topaz and fluorite are also on the ferberite sheet’s list; the other five are not.
Documented failure: the word quartz. A script search of the whole hübnerite sheet finds “Quartz” once, in “the Quartz Creek district, Gunnison Co.”, a place name. The sheet names no quartz associate, so this page makes no claim about hübnerite on or in quartz. The scheelite sheet, by contrast, names wolframite and quartz among its greisen associates, as its page records.
Ore and dust. The hübnerite sheet says it may be an ore of tungsten at some localities, and the USGS 2021 Minerals Yearbook, Tungsten calls wolframite one of two principal minerals mined for tungsten. Questions about tungsten and manganese mineral dust go to toxic minerals in a collection; this page is not safety advice. More species are in the species index. We hold no catalogue and nothing here is offered for sale; the wanted list is the only commercial route.