Comparison · Minerals
Apatite vs Calcite
Apatite and Calcite are easy to confuse because both are minerals. Apatite is harder (Mohs 5) than Calcite (Mohs 3), so Apatite 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 Apatite and Calcite
- Apatite is harder (Mohs 5) than Calcite (Mohs 3), so Apatite will scratch Calcite and not the other way round. A copper coin (Mohs 3.5) scratches it, but a fingernail does not.
- Hold a thin edge to the light: Apatite is Transparent to translucent, Calcite is transparent.
- They overlap in green, blue, yellow, and clear, but Apatite also comes in purple and brown and Calcite also comes in orange and pink.
- Well-formed crystals give it away: Apatite is Hexagonal, Calcite is trigonal.
Apatite vs Calcite properties
| Property | Apatite | Calcite |
|---|---|---|
| Type | Minerals | Minerals |
| Mohs hardness | 5 | 3 |
| Luster | Vitreous to subresinous | vitreous |
| Streak | White | White |
| Transparency | Transparent to translucent | transparent |
| Specific gravity | 3.1–3.2 | 2.7 |
| Crystal system | Hexagonal | trigonal |
| Common colors | Green, Blue, Yellow, Violet, Colorless, Brown | Colorless, White, Yellow, Orange, Blue, Green, Pink |
| Rarity | common | common |
| Typical specimen value | $2–$150+ | $2–$100+ |
Which is more valuable?
Apatite is usually the more valuable of the two: a typical collector specimen runs about $20 against $15 for Calcite, and premium Apatite can reach $150 or more.
About Apatite
Apatite is the collective name for a group of calcium phosphate minerals, chiefly hydroxylapatite, fluorapatite, and chlorapatite, sharing the general formula Ca5(PO4)3(F,Cl,OH). It is the mineral that defines hardness 5 on the Mohs scale and forms the mineral component of bones and teeth in vertebrates. Gem-quality crystals range from pale green and blue to vivid neon blue-green varieties prized by collectors.
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.
Apatite vs Calcite FAQ
Is Apatite the same as Calcite?
No. Both are minerals, but they are distinct species with different hardness, streak or luster. Apatite is harder (Mohs 5) than Calcite (Mohs 3), so Apatite 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 Apatite from Calcite?
Apatite is harder (Mohs 5) than Calcite (Mohs 3), so Apatite will scratch Calcite and not the other way round. A copper coin (Mohs 3.5) scratches it, but a fingernail does not. Hold a thin edge to the light: Apatite is Transparent to translucent, Calcite is transparent. They overlap in green, blue, yellow, and clear, but Apatite also comes in purple and brown and Calcite also comes in orange and pink.
Which is harder, Apatite or Calcite?
Apatite is harder: Mohs 5 against Mohs 3 for Calcite.
Which is more valuable, Apatite or Calcite?
Apatite is usually the more valuable of the two: a typical collector specimen runs about $20 against $15 for Calcite, and premium Apatite can reach $150 or more.
