Hemimorphite

Crystal system · Orthorhombic

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

Matched pair of pink rhodochrosite and blue hemimorphite from Yunnan, China

About Hemimorphiteextended article

Hemimorphite — zinc's sky-blue signature

Hemimorphite is a zinc silicate from the oxidized upper zones of zinc ore bodies. Its name records a genuine crystallographic oddity: the crystals are hemimorphic — the two ends of a crystal have different faces — which also makes them pyroelectric, developing opposite electrical charges when heated.

Two very different looks

Collectors meet hemimorphite in two habits: glassy, colorless fan-shaped crystal sprays, and the botryoidal crusts whose saturated sky-blue color has made the species famous. The blue botryoidal material — including the Yunnan pieces we stock — owes its color to trace copper riding along in the zinc oxidation zone.

What to look for

On botryoidal material, color saturation and an unbroken, gently rolling crust surface set the grade. Combination pieces — hemimorphite with pink rhodochrosite or cobaltoan calcite from the same carbonate zones — carry a premium.

From our inventory

See the Yunnan locality page for our botryoidal blue material, or the calcite guide for its frequent companion species.

Hemimorphite in China

China is today the world's foremost source of botryoidal blue hemimorphite. The Wenshan Mine in Yunnan Province produces rounded, grape-like crusts of vivid sky-blue to robin's-egg-blue hemimorphite — the colour caused by traces of copper — over brown matrix, sometimes with aragonite or aurichalcite. Since the 1990s these Yunnan specimens have set the standard for the species and made Chinese hemimorphite a collector favourite worldwide.

About Hemimorphite

Hemimorphite belongs to the silicate class in the hemimorphite group and has the chemical formula Zn4Si2O7(OH)2·H2O. It crystallizes in the orthorhombic system and is one of the most visually varied minerals in the collector market.

Identification & care

Crystals commonly develop as tabular, prismatic, hemimorphic (different crystal faces on each end — diagnostic!); botryoidal, stalactitic masses. Its color range is broad, including white, colorless, pale blue, pale green, and pale yellow. The luster is vitreous to resinous, the streak is white, and specimens range from transparent to translucent. The cleavage is perfect {110}. The fracture is conchoidal to uneven, which aids identification.

Collector context

Collector notes

Among collectors of crystallized species, Hemimorphite is a recognized reference. Hemimorphite is widely represented across Chinese provinces, including Hunan, Yunnan, Sichuan, Fujian.

Frequently asked questions

What is Hemimorphite?

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

What is the chemical formula of Hemimorphite?

The chemical formula of Hemimorphite is Zn4Si2O7(OH)2·H2O.

What crystal system does Hemimorphite belong to?

Hemimorphite crystallises in the Orthorhombic crystal system.

Where is Hemimorphite found?

Notable localities for Hemimorphite include Yunnan Province.

References & databases

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

Available Hemimorphite specimens

5 specimens

Recently sold Hemimorphite specimens

1 example — for reference