Comparison · Minerals
Calcite vs Chlorite
Calcite and Chlorite are easy to confuse because both are minerals. Both sit near Mohs 3, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Below is a side-by-side comparison of their properties and the quick tests that separate them.
Key differences between Calcite and Chlorite
- Both sit near Mohs 3, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
- Streak color differs: Calcite leaves a white streak on unglazed porcelain, Chlorite leaves pale green to white.
- Hold a thin edge to the light: Calcite is transparent, Chlorite is Translucent.
- They overlap in green, but Calcite also comes in clear, yellow, orange, blue, and pink and Chlorite also comes in black.
- Well-formed crystals give it away: Calcite is trigonal, Chlorite is Monoclinic.
Calcite vs Chlorite properties
| Property | Calcite | Chlorite |
|---|---|---|
| Type | Minerals | Minerals |
| Mohs hardness | 3 | 2–2.5 |
| Luster | vitreous | Vitreous to pearly |
| Streak | White | Pale green to white |
| Transparency | transparent | Translucent |
| Specific gravity | 2.7 | 2.6–3.3 |
| Crystal system | trigonal | Monoclinic |
| Common colors | Colorless, White, Yellow, Orange, Blue, Green, Pink | Green, Dark green, Blackish green |
| Rarity | common | common |
| Typical specimen value | $2–$100+ | $2–$150+ |
Which is more valuable?
Chlorite is usually the more valuable of the two: a typical collector specimen runs about $20 against $15 for Calcite, and premium Chlorite 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 Chlorite
Chlorite is not a single mineral but a large group of iron- and magnesium-rich phyllosilicates, including clinochlore and chamosite, sharing a layered sheet-silicate structure related to mica. Its name refers to its typical dull to bright green color, caused by iron and magnesium within the crystal lattice. It is one of the most common minerals in low-grade metamorphic rocks.
Calcite vs Chlorite FAQ
Is Calcite the same as Chlorite?
No. Both are minerals, but they are distinct species with different hardness, streak or luster. Both sit near Mohs 3, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
How can you tell Calcite from Chlorite?
Both sit near Mohs 3, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Streak color differs: Calcite leaves a white streak on unglazed porcelain, Chlorite leaves pale green to white. Hold a thin edge to the light: Calcite is transparent, Chlorite is Translucent.
Which is harder, Calcite or Chlorite?
Calcite is harder: Mohs 3 against Mohs 2–2.5 for Chlorite.
Which is more valuable, Calcite or Chlorite?
Chlorite is usually the more valuable of the two: a typical collector specimen runs about $20 against $15 for Calcite, and premium Chlorite can reach $150 or more.
