What aragonite is
Aragonite is one of the three natural crystal forms of calcium carbonate, with calcite and vaterite. Same chemistry, different arrangement of atoms: aragonite is orthorhombic, slightly harder and denser than calcite, and thermodynamically unstable at the surface, so over geological time it slowly turns into calcite.
It forms through both physical and biological processes. Pearls, coral skeletons and the inner nacre of many shells are aragonite. In rocks it grows as needles, columns, cave formations and twinned crystals that look hexagonal.
Aragonite from Morocco
Moroccan aragonite is sold mostly as radiating clusters of brown, orange or reddish twinned crystals, marketed as star or sputnik aragonite and often labelled with the locality Tazouta. Dealers also list Moroccan aragonite stalactites, some described as phosphorescent.
What aragonite costs: price data from October 2026
Asking prices read on 28 October 2026.
| Source | Listings | Price |
|---|---|---|
| eBay, Moroccan aragonite, fixed price | 146 | Median $20, middle half $12 to $33 |
| eBay, highest listing | $240 |
How to judge and care for aragonite
Look for a full, symmetrical cluster, sharp crystal tips and rich colour.
- Aragonite is soft (3.5 to 4) and the radiating points break easily.
- Like calcite, it dissolves in acids: never clean with vinegar or lemon.
- Rinse in plain water if needed and dry well.
Questions collectors ask
What is the difference between aragonite and calcite?
Both are calcium carbonate. Aragonite has an orthorhombic structure and is a little harder and denser; calcite is trigonal and more stable. Aragonite slowly turns into calcite.
Is Moroccan aragonite natural?
Yes. The brown radiating 'sputnik' clusters are natural twinned aragonite crystals.
How much is aragonite worth?
On 28 October 2026, fixed-price eBay listings for Moroccan aragonite had a median asking price of $20.