What's That Rock?Aragonite
A calcium carbonate with the same chemistry as calcite but a different structure. Pearls and many shells are made of it.
How to identify Aragonite
- Heavier than calcite for the same size
- Needle-like or branching crystals, often in clusters
- Fizzes in dilute acid
Often confused with
Is Aragonite valuable?
Inexpensive.
Typical retail prices
Collector specimen$5–60each
Typical retail ranges in US dollars, compiled from public dealer and marketplace listings in October 2026. Real prices vary widely with quality, size and origin. This is general information, not an appraisal.
What changes the price
- Form: sputnik clusters, flos ferri 'coral' and colored crystals are the sought-after types
- Color and sharpness: clean, bright, undamaged crystals cost more
- Fragile: broken clusters are common and worth less
- Pearls and shells are made of aragonite but are valued as pearls and shells
Uses
- Specimens, shells and pearls are aragonite
Care
Soft. Avoid acids, heat and humidity.
Identifying a stone from a description or a photo is an estimate. Many stones look alike. Ask an expert or a gem lab before you buy, sell or rely on an identification.
Updated October 2026