Identity
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Name & Human History
Etymology
Hubnerite is a tungsten mineral, made of manganese and tungsten and oxygen. It forms striking blades, deep reddish brown to brownish black, often with a bright, almost resinous shine. Held to the light, thin crystals can glow a rich red. The mineral was named for Adolf Hubner, a German mining expert of the 1800s. Its name is said roughly as HUEB-ner-ite.
Today
Hubnerite is valued as an ore of tungsten, one of the toughest of all metals. Tungsten resists heat and wear like almost nothing else, so it goes into cutting tools, drill bits, and the glowing filaments of older light bulbs. Collectors, meanwhile, prize hubnerite for its crystals. The best are slender, bladed, and translucent, glowing red when light passes through their edges.
Geology & Occurrence
Formation
Hubnerite forms in veins from very hot fluids, often the same veins that carry tin and tungsten near granite. It grows with quartz, and often beside cassiterite, the main tin ore, along with pyrite and other vein minerals. The crystals tend to be bladed and grooved, and they are usually scattered through milky white quartz like dark splinters of wood in ice.
Notable Localities
The finest hubnerite in the world comes from Peru. The Pasto Bueno district and the Mundo Nuevo mine have produced superb bladed crystals, bright and sharp, the best known anywhere. Good hubnerite also comes from Colorado and Arizona in the United States, and from a few mines in China. But the Peruvian crystals are the ones collectors dream of.
Hubnerite is one end of a mineral pair. It and a sister mineral, ferberite, form a smooth series. Where the metal is manganese, you get reddish hubnerite, and where it is iron, you get black ferberite. Mixtures in between are called wolframite, long a key ore of tungsten. So hubnerite is really the bright, manganese rich end of the old wolframite story.
