Mimetite

Crystal system · Hexagonal

Mimetite is a phosphate mineral prized by collectors for its exceptional color range, with known Chinese sources.

Mimetite specimen
Photo: Ivar Leidus · CC BY-SA 4.0 via Wikimedia Commons

About Mimetiteextended article

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China is a defining locality for Mimetite · 砷铅矿. See the Chinese collector page →

Elemental Composition (by mass)
ElementMass %Visual
Pb Lead69.61%
As Arsenic15.10%
O Oxygen12.90%
Cl Chlorine2.38%
Computed from simplified end-member formula. Solid-solution series, water content, and trace substitutions cause real-world variation.
IMA Abbreviation (Whitney-Evans 2010)
Mmt
→ Mimetite
Pb chloroarsenate
Standard symbol from American Mineralogist (Whitney & Evans, 2010). Used in thin-section labeling, phase diagrams, and IMA-style species records.
Pronunciation
/ˈmɪmɪtaɪt/
MIM-ih-tite
Greek mimetes (imitator)
⚠ Safety & Handling
toxichigh
Lead chloroarsenate — both Pb and As content.
Handling: Wash hands. No grinding/polishing.
Information provided in good faith. Consult local hazmat regulations for transport and disposal. Severely hazardous specimens may require special storage cabinets.
Specific Gravity
7.15–7.27
g/cm³
very heavy
Pb chloroarsenate.
For comparison: water = 1.00, glass ≈ 2.5, quartz = 2.65, corundum ≈ 4.00, galena ≈ 7.50, gold ≈ 19.3.
Streak Test
white
White streak — diagnostic Pb-As mineral.
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.
Mohs 3.5–4
Vickers (~) 200 HV
Knoop (~) 220 HK
Element composition by mass

Formula: Pb₅(AsO₄)₃Cl · molar mass: 1488.2 g/mol

Pb 69.61%
As 15.1%
O 12.9%
Cl 2.38%

Computed from atomic weights (IUPAC 2021). Site-occupancy groups (Fe,Mn) split equally.

Mohs Hardness 3.5–4

Mimetite sits at 3.5–4 on the Mohs scale — can be scratched by a steel knife.

Colors:
Streak
White
Crystal system
Hexagonal
PhosphatesPhosphates (Arsenates)
TL;DR · 1 min read
Mimetite (Pb₅(AsO₄)₃Cl) is the arsenate analog of pyromorphite — yellow to orange hexagonal crystals from oxidized lead-arsenic ore zones. The "campylite" variety forms characteristic barrel-shaped, curved crystals.

Mimetite (Pb₅(AsO₄)₃Cl) is the arsenate analog of pyromorphite — yellow to orange hexagonal crystals from oxidized lead-arsenic ore zones. The “campylite” variety forms characteristic barrel-shaped, curved crystals. Bayan Obo (Inner Mongolia) hosts notable specimens alongside REE-bearing minerals.

Notable Chinese Localities

Bayan Obo Mine (Inner Mongolia) is the principal Chinese source. Daoping (Guangxi) produces mimetite alongside pyromorphite.

Cite this entry
APA
MyMineralBox Editorial Team. (2026). Mimetite. My Mineral Box. Retrieved May 23, 2026, from https://mymineralbox.com/mineral-encyclopedia/minerals/mimetite/
MLA
MyMineralBox Editorial Team. "Mimetite." My Mineral Box, 2026, https://mymineralbox.com/mineral-encyclopedia/minerals/mimetite/. Accessed May 23, 2026.
Chicago
MyMineralBox Editorial Team. "Mimetite." My Mineral Box. Last modified May 4, 2026. https://mymineralbox.com/mineral-encyclopedia/minerals/mimetite/.
BibTeX
@misc{mmb_mimetite,
 author = {{MyMineralBox Editorial Team}},
 title = {{Mimetite}},
 year = {2026},
 publisher = {My Mineral Box},
 url = {https://mymineralbox.com/mineral-encyclopedia/minerals/mimetite/},
 urldate = {2026-05-23}
}

About Mimetite

Mimetite belongs to the phosphate class in the apatite supergroup (pyromorphite group) and has the chemical formula Pb5(AsO4)3Cl. It crystallizes in the hexagonal system and is one of the most visually varied minerals in the collector market. Its combination of structural character and global distribution make it a recognized species in both systematic and aesthetic collections.

Identification & care

Mimetite typically forms prismatic hexagonal crystals (barrel-shaped 'campylite' variety); globular clusters; botryoidal; acicular. Its color range is broad, including yellow, pale yellow, yellowish orange, white, colorless, brownish, and rarely green. The luster is resinous, sub-adamantine, the streak is white, and specimens range from translucent to transparent. The cleavage is imperfect on {10-11}. The fracture is subconchoidal to uneven, which aids identification.

Collector context

How it forms

In terms of geology, Mimetite forms in oxidized zone of lead-arsenic ore deposits; rare secondary mineral in gossans. It is commonly found in association with pyromorphite, vanadinite, cerussite, wulfenite, limonite, galena.

Classic Chinese localities

Mimetite is widely represented across Chinese provinces, including Hunan, Yunnan, Inner Mongolia, Hubei.

Why collectors care

Mimetite is a frequently-sought species in serious collections because its habit is recognizable, its color often strong, and its best examples unmistakable even at a distance. Chinese material has driven much of the recent visual shift in the species — sharper crystals, deeper colors, cleaner matrix.

What affects value

Value in Mimetite is assessed, in typical order of weight, against: (1) locality provenance; (2) size relative to the species norm; (3) crystal form and termination sharpness; (4) color saturation and zoning; (5) transparency and internal clarity; (6) matrix quality and aesthetic balance; (7) condition (absence of damage, chips, or repair). Cleaning quality and verified locality documentation act as multipliers across the above.

Naming history

The name Mimetite has a specific etymological and historical context — see Mindat's reference entry for provenance details. We have retained naming data at the record level; published prose is paraphrased from factual fields rather than copied from source.

Frequently asked questions

What is Mimetite?

Mimetite is a phosphate mineral prized by collectors for its exceptional color range, with known Chinese sources.

What is the chemical formula of Mimetite?

The chemical formula of Mimetite is Pb5(AsO4)3Cl.

What crystal system does Mimetite belong to?

Mimetite crystallises in the Hexagonal crystal system.

Where is Mimetite found?

Notable localities for Mimetite include Daoping Mine, Tsumeb, Ojuela / Mapimí.

References & databases

Mindat.org is the world’s largest open mineralogy database. Our descriptions are written independently and fact-checked.