Overview

Stibnite (antimony sulfide, Sb2S3) is one of the most dramatic metallic species in the mineral world. It forms sword-like, prismatic crystals with pronounced longitudinal striations and a brilliant, steel-gray metallic luster that can verge on mirror-bright. Crystals range from delicate acicular sprays to robust lances several centimeters thick, and in rare cases over a meter long. Fans, radiating “hedgehogs,” and elegant intergrown clusters on white calcite or quartz matrix are classics. Fresh, untarnished stibnite shows a gunmetal sheen; with time, it may develop a soft patina or subtle iridescence.

Collectors value stibnite for its striking aesthetics, iconic “swords,” and the lore of historic localities like Ichinokawa in Japan, where the largest crystals ever found set a standard still referenced today. Modern Chinese and Eastern European discoveries have kept superb examples available, while select older pieces command major premiums. Despite its softness and fragility (Mohs ~2), the visual impact of top stibnite ensures it remains a cornerstone of metallic mineral collections.

Popularity

Stibnite has been mined for antimony since antiquity, but its desirability as a collector mineral surged in the 19th century when extraordinary, meter-scale crystals from Ichinokawa stunned Europe’s museums and salons. In the late 20th and early 21st centuries, a wave of Chinese material—especially from Hunan—reinvigorated the market with spectacular, lustrous clusters at a variety of sizes and price points.

Romanian classics from Herja and Cavnic and Italian pieces from Pereta contribute timeless aesthetics—radiating sprays and elegant groupings often on calcite. Peruvian material from Pasto Bueno added refined, sharply striated crystals in tasteful compositions. Kyrgyz and other Central Asian sources are prized for robust, silvery lances and distinctive forms. Today, collectors at all levels can access stibnite: from modest small sprays to landmark, museum-grade “swords” that are few, famed, and fiercely sought.

Top Collecting Localities

The following localities are renowned for producing stibnite that has shaped collector standards. Each is linked to a dedicated guide and includes a map and gallery of examples.

Ichinokawa Mine, Japan

Type-locality fame and unmatched scale define Ichinokawa (Shikoku). The mine produced some of the largest, most perfect stibnite crystals ever found—gleaming, sword-like lances with textbook striations and razor terminations, many measuring tens of centimeters and historic giants far beyond. Most examples are old classics, often with soft patina from age. Large, balanced clusters with undamaged tips are exceedingly rare and command elite prices; even small, pristine single crystals fetch strong premiums due to provenance. These pieces set the canonical ideal for stibnite crystal form, luster, and presence.

Xikuangshan Sb Deposit, China

The world’s largest antimony deposit, Xikuangshan (Hunan) is synonymous with modern stibnite. Since the 1990s, it has produced superb clusters of brilliant, silvery crystals—thick lances and fine needles alike—often in radiating sprays or intersecting groups. Many are on calcite or dolomite, creating striking light–dark contrast. Specimens range widely in size, and while the mine has yielded significant quantities, truly top aesthetics with sharp terminations and minimal damage remain coveted. For many collectors, Xikuangshan defines the contemporary standard for display-quality stibnite.

Herja Mine, Romania

Herja (Baia Mare district, Maramureș County) is renowned for starburst sprays and aesthetic clusters of stibnite, frequently on or with snowy calcite that creates superb contrast. Crystals are usually slender, with a bright to silky luster. The mine produced a range of sizes, and while small sprays abound, cabinet pieces with crisp terminations and undamaged radiations are sought after. Old Romanian specimens remain in demand for their display elegance and classic provenance.

Collector’s Guide

Evaluating Specimen Quality

• Luster and Surface Freshness: The hallmark of great stibnite is a bright metallic sheen—ideally mirror-like on prism faces, with crisp longitudinal striations. Dull or matte surfaces, heavy tarnish, or corrosion films lower impact (though a soft antique patina can be attractive on historic pieces). Avoid sandblasted or artificially polished looks.

• Crystal Form and Terminations: Seek well-formed, straight, prismatic crystals with sharp terminations. Bent, kinked, or “mushroomed” tips often indicate damage or internal stress. In clusters, evenly radiating sprays and intersecting lances that display from multiple angles are especially aesthetic.

• Size and Proportion: Length is a major value driver, but proportion matters: a single 10–15 cm sword with perfect tip and brilliant luster can outshine a longer but battered crystal. Balanced clusters—graduated crystal lengths, slight splay, and elegant geometry—are highly desirable.

• Damage and Repairs: Stibnite is very soft (Mohs ~2) and brittle. Inspect tips, edges, and intersections carefully for chips or breaks. Look closely where crystals meet the matrix; reattachments are common. A single, expertly done, disclosed repair can be acceptable on significant pieces, but multiple or obtrusive fixes reduce value.

• Aesthetic Associations: White calcite, quartz, or dolomite matrix provides dramatic contrast. Clean, complementary associations enhance appeal; heavy, etched, or stained matrix can distract unless it contributes to a historic “look” (e.g., classic Herja calcites).

• Color/Tarnish: Fresh steel-gray is prized; subtle blue-purple iridescence can be a plus. Heavy bronze oxidation or patchy alteration to oxides (stibiconite) detracts unless the piece is historically important.

• Provenance: Labels from iconic localities (Ichinokawa, Pereta, Herja, Pasto Bueno, Xikuangshan) and references to noted pockets or old collections can significantly boost desirability.

Detecting Repairs or Treatments

• Reattachment Lines: Use a 10x loupe to scan along crystals and where they meet matrix. Perfectly straight seams, slight misalignments in striations, a glossy film, or occasional bubbles under UV can indicate epoxy.

• Hidden Supports: Some large crystals are stabilized with pins or wires drilled into matrix. Look for tiny drill holes or non-natural “bridges” at the base or back of clusters.

• Coatings: Clear lacquer, wax, or oil can enhance luster or slow tarnish. Uneven sheen, dust trapped in a film, or a slightly “plastic” look are clues. Mild solvent on a swab (tested away from critical areas) may reveal a coating, but test very cautiously.

• Polished or Sawed Ends: A razor-flat, mirror-bright termination with no growth features could be polished. Natural terminations usually show minute growth textures or tiny, aligned micro-steps.

• Fakes: Rare; cast metal copies lack natural striations and display mold artifacts or bubbles. Stibnite is very soft and leaves a gray streak; artificial pieces typically feel “wrong” and lack natural growth lines.

Care and Storage

Stibnite is soft, brittle, and can tarnish—gentle handling and a stable, dry environment are key.

• Handling:

  • Support from the base/matrix; avoid touching tips or thin sections.
  • Use two hands for larger pieces; do not flex slender crystals—they will snap.
  • Wash hands after handling (antimony compounds are toxic if ingested; avoid rubbing eyes or mouth).

• Environment:

  • Keep dry and cool. Use a dust-proof display case; consider low-humidity storage with silica gel if you live in a humid climate to slow tarnish and oxidation.
  • Avoid direct sun and heat sources—thermal changes can stress or crack clusters and may accelerate tarnish.
  • Gentle LED case lighting is ideal.

• Cleaning:

  • Prefer dry methods: a soft blower, camel-hair or makeup brush. Do not use ultrasonic or steam cleaners.
  • If necessary, a barely damp microfiber swab can lift fingerprints, but keep water exposure minimal and dry immediately.
  • Avoid acids and aggressive chemicals; they can damage stibnite or its matrix (calcite dissolves in acid; coatings can turn patchy).

• Stabilization:

  • If a piece has known, disclosed stabilization (epoxy joins, pins), avoid soaking or heat which can compromise adhesives.
  • To slow tarnish, some collectors use inert display cases or micro-environments; applying coatings is generally discouraged for top specimens and should be disclosed if present.

• Storage & Transport:

  • Store individually in padded boxes or trays; stibnite scratches and breaks easily.
  • Do not allow heavier specimens to contact delicate clusters.
  • For quake-prone areas or travel, use custom foam cavities; avoid vibration and jostling.

By focusing on brilliant luster, sharp terminations, elegant composition, and sound condition—and by caring for pieces gently in dry, stable conditions—you can assemble and preserve a compelling suite of stibnite ranging from classic historic swords to modern, radiant sprays.