Huebnerite is a distinctive member of the wolframite group of minerals that draws attention both from industrial geologists and mineral collectors. This mineral, whose chemistry centers on manganese and tungsten, forms striking prismatic crystals and aggregates in a variety of hydrothermal and metamorphic settings. In this article I examine its mineralogical characteristics, typical geological environments, […]
Hornblende is a common and scientifically important rock-forming mineral from the amphibole group. Its dark, elongated crystals appear across a wide range of geological settings and serve as a recorder of the physical and chemical conditions under which rocks form and transform. In this article I discuss its composition and physical properties, where it is
Hollandite is a distinctive member of the manganese oxide family, recognizable by its characteristic tunnel framework and complex chemistry. It is important both as a naturally occurring mineral in diverse geological settings and as a model and functional material in modern technology. This article explores where hollandite is found, how its structure and composition influence
Hillebrandite is a little-known but scientifically significant mineral belonging to the family of natural calcium‑silicate‑hydrate phases. Although it is relatively rare in hand‑sample form, it occupies an outsized place in the study of metamorphic processes, skarn geology, and the geochemistry of cementitious materials. This article explores the mineral’s defining characteristics, the geological settings where it
Hiddenite is a striking green variety of the mineral spodumene prized for its vibrant color, crystal clarity, and geological story. Although often overshadowed in popular awareness by emerald and tourmaline, hiddenite occupies an important place in both the world of gemology and the study of pegmatitic mineral deposits. This article explores the origin, physical and
The term Herkimer Diamond evokes images of brilliantly clear, naturally faceted gems that sparkle as though cut by a jeweler’s hand. Despite the name, these are not diamonds but exceptional specimens of quartz that form with perfectly terminated points and remarkable clarity. Their story is one of unique geological conditions, local mining traditions, enthusiastic collectors,
Helvite is a fascinating and visually striking mineral whose story spans geology, mineral collecting and the study of rare-element deposits. Often admired for its warm, amber to brown tones and its association with beryllium-rich environments, helvite occupies a niche interest among mineralogists and collectors. This article explores its origin, chemistry, geological settings, physical properties, practical
Heliodor is a captivating variety of the mineral beryl, admired for its warm, **golden** to yellow-green hues and its striking crystalline forms. This article explores the mineralogical identity of heliodor, the geological environments where it is found, its practical and aesthetic applications, and a range of cultural, historical and trade-related topics connected with this gemstone.
Hauyne is a striking and scientifically significant mineral best known for its vibrant blue shades and its membership in the broader family of framework silicates. As a distinctive representative of the sodalite group, hauyne attracts interest from mineral collectors, gem cutters, and petrologists alike. This article explores its mineralogical characteristics, the geological settings where it
Hanksite is an unusual and visually striking mineral that captures the attention of mineralogists, geochemists and collectors alike. It is notable not only for its aesthetic qualities—often forming large, pale yellow crystals—but also for its rare combination of chemical components and the specific environmental conditions required for its formation. This article explores where hanksite is
