Crystal & mineral guide
Chrysocolla
(Cu,Al)₂H₂Si₂O₅(OH)₄·nH₂O
Soft blue-green copper silicate — field indicator of copper oxidation.
Identify Chrysocolla with RockScanAbout Chrysocolla
Chrysocolla forms botryoidal blue-green crusts in copper oxide zones. Often mixed with quartz or malachite for durability in jewelry (gem silica is chrysocolla-in-quartz). Soft pure material is fragile. Eilat stone historically mixes chrysocolla with related copper minerals.
Chrysocolla belongs in a crystal identifier workflow because photo cues — color zoning, crystal habit, and surface luster — combine with measurable traits like Mohs 2–4 and specific gravity 2.0–2.4. Use RockScan’s camera to get a first-pass ID, then confirm with the checklist below.
Chrysocolla properties
| Mohs hardness | 2–4 |
|---|---|
| Crystal system | Orthorhombic (cryptocrystalline) |
| Luster | Vitreous to earthy |
| Color | Blue to blue-green |
| Composition | Hydrated copper aluminum silicate |
| Formation | Oxidation zones of copper deposits |
| Occurrence | Arizona, Peru, DRC, Israel (Eilat stone mixes) |
| Specific gravity | 2.0–2.4 |
| Cleavage | None |
How to identify Chrysocolla
- Sky blue-green botryoidal crusts
- Soft — often stabilized or quartz-hosted for jewelry
- Associates with malachite/azurite
Collector notes
- Name means 'gold glue' from ancient soldering use claims
- Gem silica from Arizona is the premium jewelry form
Value context: Hard gem silica (chrysocolla in quartz) far outprices soft pure material.
Chrysocolla FAQ
How do you identify Chrysocolla?
Chrysocolla ((Cu,Al)₂H₂Si₂O₅(OH)₄·nH₂O) is typically recognized by blue to blue-green color, vitreous to earthy luster, Mohs hardness 2–4, and orthorhombic (cryptocrystalline) crystal system. RockScan can suggest Chrysocolla from a photo and surface these checks on the result card.
What is Chrysocolla made of?
Chrysocolla composition: Hydrated copper aluminum silicate. It forms via oxidation zones of copper deposits and is found in Arizona, Peru, DRC, Israel (Eilat stone mixes).
Is Chrysocolla valuable?
Hard gem silica (chrysocolla in quartz) far outprices soft pure material.
