Comparison · Minerals
Calcite vs Hemimorphite
Calcite and Hemimorphite are easy to confuse because both are minerals. Hemimorphite is harder (Mohs 4.5–5) than Calcite (Mohs 3), so Hemimorphite will scratch Calcite and not the other way round. A copper coin (Mohs 3.5) scratches it, but a fingernail does not. Below is a side-by-side comparison of their properties and the quick tests that separate them.
Key differences between Calcite and Hemimorphite
- Hemimorphite is harder (Mohs 4.5–5) than Calcite (Mohs 3), so Hemimorphite will scratch Calcite and not the other way round. A copper coin (Mohs 3.5) scratches it, but a fingernail does not.
- Hemimorphite feels noticeably heavier for its size (specific gravity 3.4–3.5 versus 2.7 for Calcite).
- Hold a thin edge to the light: Calcite is transparent, Hemimorphite is Transparent to translucent.
- They overlap in clear, yellow, blue, and green, but Calcite also comes in orange and pink and Hemimorphite also comes in brown.
- Well-formed crystals give it away: Calcite is trigonal, Hemimorphite is Orthorhombic.
Calcite vs Hemimorphite properties
| Property | Calcite | Hemimorphite |
|---|---|---|
| Type | Minerals | Minerals |
| Mohs hardness | 3 | 4.5–5 |
| Luster | vitreous | Vitreous, silky when fibrous |
| Streak | White | White |
| Transparency | transparent | Transparent to translucent |
| Specific gravity | 2.7 | 3.4–3.5 |
| Crystal system | trigonal | Orthorhombic |
| Common colors | Colorless, White, Yellow, Orange, Blue, Green, Pink | White, Colorless, Pale blue, Green, Brown, Yellowish |
| Rarity | common | common |
| Typical specimen value | $2–$100+ | $2–$150+ |
Which is more valuable?
Hemimorphite is usually the more valuable of the two: a typical collector specimen runs about $20 against $15 for Calcite, and premium Hemimorphite can reach $150 or more.
About Calcite
Calcite is one of the most common minerals on Earth, found in sedimentary, metamorphic, and igneous rocks. It's the primary component of limestone and marble.
About Hemimorphite
Hemimorphite is a zinc silicate hydroxide mineral crystallizing in the orthorhombic system and named for its hemimorphic crystals, which develop different faces at opposite ends of the same crystal axis. It typically forms in the oxidized zones of zinc ore deposits, often intergrown with or resembling smithsonite, another secondary zinc mineral. Its delicate, fan-shaped crystal clusters and pastel blue to white coloring make it a favorite among collectors of secondary zinc minerals.
Calcite vs Hemimorphite FAQ
Is Calcite the same as Hemimorphite?
No. Both are minerals, but they are distinct species with different hardness, streak or luster. Hemimorphite is harder (Mohs 4.5–5) than Calcite (Mohs 3), so Hemimorphite will scratch Calcite and not the other way round. A copper coin (Mohs 3.5) scratches it, but a fingernail does not.
How can you tell Calcite from Hemimorphite?
Hemimorphite is harder (Mohs 4.5–5) than Calcite (Mohs 3), so Hemimorphite will scratch Calcite and not the other way round. A copper coin (Mohs 3.5) scratches it, but a fingernail does not. Hemimorphite feels noticeably heavier for its size (specific gravity 3.4–3.5 versus 2.7 for Calcite). Hold a thin edge to the light: Calcite is transparent, Hemimorphite is Transparent to translucent.
Which is harder, Calcite or Hemimorphite?
Hemimorphite is harder: Mohs 4.5–5 against Mohs 3 for Calcite.
Which is more valuable, Calcite or Hemimorphite?
Hemimorphite is usually the more valuable of the two: a typical collector specimen runs about $20 against $15 for Calcite, and premium Hemimorphite can reach $150 or more.
