Crystal Structure
Zincblende structure — Zn + S each in FCC arrays.
Elemental Composition (by mass)
| Element | Mass % | Visual |
|---|---|---|
| Zn Zinc | 67.10% | |
| S Sulfur | 32.90% |
Computed from simplified end-member formula. Solid-solution series, water content, and trace substitutions cause real-world variation.
IMA Abbreviation (Whitney-Evans 2010)
Sp
→ Sphalerite
Zn sulfide
Standard symbol from American Mineralogist (Whitney & Evans, 2010). Used in thin-section labeling, phase diagrams, and IMA-style species records.
Pronunciation
/ˈsfælərˌaɪt/
↔ SFAL-uh-rite
Greek "treacherous"
Lapidary & Faceting Recommendations
Recommended cut:
round brilliant
Also seen:
oval, cushion
Typical yield:
20% of rough
Extreme dispersion 0.156 (3x diamond) gives spectacular fire — but Mohs 3.5 too soft for jewelry use. Collector-grade only.
⚠ Safety & Handling
☠toxiclow
Mostly stable; trace cadmium in Cd-rich varieties.
Handling: Wash hands after extended handling.
Information provided in good faith. Consult local hazmat regulations for transport and disposal. Severely hazardous specimens may require special storage cabinets.
Luster
adamantine→resinous
High-RI sphalerite has adamantine; Fe-rich varieties more resinous.
Diaphaneity (Transparency)
transparent-to-opaque
Gem-grade transparent (Las Mañas); Fe-rich opaque (marmatite).
Type Locality
(ancient — Greek "sphaleros" = treacherous) — Germany
Described 1847 by Glocker
Magnetism
Category:
weakly paramagnetic
Test result:
Detectable (Fe-rich)
Fe-rich (marmatite) variety strongly paramagnetic.
Test with rare-earth magnet (N42 or N52 neodymium). Suspend specimen on thread for sensitive paramagnetic detection. Diamagnetic minerals are weakly repelled (visible only with strong magnets like bismuth).
Diagnostic Field Tests
Smell→ Rotten egg (H₂S) when struck
Zn sulfide — H₂S released from fresh fractures.
UV test→ Fluoresces orange-red (some specimens)
Phosphorescent material from Franklin NJ.
⚠ Use dilute HCl (~10%) only on inconspicuous spots; rinse promptly. Smell-tests should be brief and ventilated. Taste-test ONLY halite/sylvite — never lead, arsenic, or sulfur minerals.
Specific Gravity
3.90–4.10
g/cm³
heavy
High variability with Fe content.
For comparison: water = 1.00, glass ≈ 2.5, quartz = 2.65, corundum ≈ 4.00, galena ≈ 7.50, gold ≈ 19.3.
Streak Test
brown / yellow
Fe content shifts streak from pale yellow (low-Fe) to brown (high-Fe).
Streak = color of the powdered mineral. Drag specimen across unglazed white porcelain plate (Mohs 6.5). For minerals harder than the plate, crush a small flake into powder and observe color.
Geological Setting
Environment:
hydrothermal
Host rock:
hydrothermal vein, Mississippi Valley type, volcanogenic massive sulfide
Companions:
Gemmy sphalerite from Spain (Aliva, Las Mañas) — Mn-rich red-orange material.
Cleavage & Fracture
Cleavage:
perfect 6 directions {110} — dodecahedral
Fracture:
conchoidal
Six perfect dodecahedral cleavages — diagnostic.
Market availability: Common
Widely available in most dealer stocks. Specimens span all price tiers.
Collector tier: Cabinet Classic
World-class display species — sought after for cabinet collections, well-documented localities, frequent show-piece pieces.
PolymorphsShares the formula
ZnS with: Wurtzite — same chemistry, different crystal structure.Mohs 3.5–4
Vickers (~) 200 HV
Knoop (~) 220 HK
Nickel–Strunz
2.CB.05aDana
02.08.02.01Geological setting
Hydrothermal
Element composition by mass
Formula: (Zn,Fe)S · molar mass: 92.67 g/mol
| Zn | 35.27% | |
| S | 34.59% | |
| Fe | 30.13% |
Computed from atomic weights (IUPAC 2021). Site-occupancy groups (Fe,Mn) split equally.
Mohs Hardness
3.5–4
Sphalerite sits at 3.5–4 on the Mohs scale — can be scratched by a steel knife.
Colors:
Streak
Brown to pale yellow
Brown to pale yellow
Crystal system
Isometric (Cubic)
Isometric (Cubic)
Pronunciation/ˈsfælərˌaɪt/
Type localityPříbram, Bohemia, Czech Republic
Sulfides & SulfosaltsSulfides
TL;DR · 1 min read
Sphalerite is the world's primary ore of zinc and the source of nearly all collectable Zn-bearing crystal specimens. Its (Zn,Fe)S chemistry produces the full color range from honey-yellow "cleiophane" through ruby-red "marmatite" to opaque iron-rich black.
Sphalerite is the world’s primary ore of zinc and the source of nearly all collectable Zn-bearing crystal specimens. Its (Zn,Fe)S chemistry produces the full color range from honey-yellow “cleiophane” through ruby-red “marmatite” to opaque iron-rich black. Tetrahedral and dodecahedral crystal forms with adamantine luster make sphalerite a perennial collector favorite.
Notable Chinese Localities
Dexing (Jiangxi) and Daye (Hubei) produce dark high-Fe sphalerite as porphyry copper byproduct. Yaogangxian (Hunan) and Huanggang (Inner Mongolia) yield gemmy crystals up to several cm.
Cite this entry
APA
MyMineralBox Editorial Team. (2026). Sphalerite. My Mineral Box. Retrieved May 23, 2026, from https://mymineralbox.com/mineral-encyclopedia/minerals/sphalerite/
MLA
MyMineralBox Editorial Team. "Sphalerite." My Mineral Box, 2026, https://mymineralbox.com/mineral-encyclopedia/minerals/sphalerite/. Accessed May 23, 2026.
Chicago
MyMineralBox Editorial Team. "Sphalerite." My Mineral Box. Last modified May 4, 2026. https://mymineralbox.com/mineral-encyclopedia/minerals/sphalerite/.
BibTeX
@misc{mmb_sphalerite,
author = {{MyMineralBox Editorial Team}},
title = {{Sphalerite}},
year = {2026},
publisher = {My Mineral Box},
url = {https://mymineralbox.com/mineral-encyclopedia/minerals/sphalerite/},
urldate = {2026-05-23}
}
