RocksdayRhodochrosite vs Rhodonite
How to tell them apart
A manganese carbonate in raspberry-red crystals or rose-and-white banded stalactites.
Photo: JJ Harrison (https://www.jjharrison.com.au/), CC BY-SA 4.0
A rose-pink manganese silicate usually laced with black veins of manganese oxide.
Photo: CarlesMillan, CC BY-SA 4.0
Quick tests
- Hardness: Rhodonite is clearly harder: Mohs 5.5–6.5 versus 3.5–4.
- Acid (vinegar or dilute HCl): Rhodochrosite fizzes weakly, or only when powdered or warmed; Rhodonite doesn't.
Key differences
- Rhodochrosite is softer, banded and fizzes in warm acid.
Side by side
| Property | Rhodochrosite | Rhodonite |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 3.5–4 | 5.5–6.5 |
| Luster | Vitreous | Vitreous |
| Streak | White | White |
| Colors | Pink, Red | Pink, Red, Black |
| Crystal system | Trigonal | Triclinic |
| Specific gravity | 3.5–3.7 | 3.4–3.7 |
| Formula | MnCO₃ | (Mn,Fe,Mg,Ca)SiO₃ |
| Found in | Capillitas, Argentina; Sweet Home Mine, Colorado | Ural Mountains, Russia; Broken Hill, Australia |
Properties that are the same for both are grayed out.
How to identify rhodochrosite
- Rose-pink to red, often banded.
- Rhomb-shaped crystals and cleavage.
- Fizzes in warm acid.
- Soft — a knife scratches it.
Crystal system: Trigonal
Full Rhodochrosite guide →How to identify rhodonite
- Pink to raspberry with black veins or patches.
- Hardness about 6 — scratches glass slightly.
- Does not fizz in acid.
Crystal system: Triclinic
Full Rhodonite guide →More comparisons
Could you tell them apart from a blurry close-up?
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