KhyatiGems knowledge library
Moonstone
Moonstone belongs to the feldspar family. Its characteristic moving sheen is called adularescence and is associated with its internal structure.
AI-assisted source review · 2026-10-16. No named gemologist review is claimed. How this reference was reviewed.
Meganpru · CC BY-SA 3.0 · Source · CC BY-SA 3.0
| Material classification | Feldspar |
|---|---|
| Mohs hardness (reference) | 6–6.5 |
Identity and appearance
Moonstone belongs to the feldspar family. Its characteristic moving sheen is called adularescence and is associated with its internal structure.
A blue sheen is an appearance observation, not proof of origin or identity. Trade labels may cover different feldspar materials, so request the actual identification.
Care and handling
Protect cabochon surfaces and avoid ultrasonic and steam cleaning. Inspect the setting and any fractures before adopting a cleaning routine.
Questions for an individual stone
Keep the material name, natural or laboratory-grown origin, treatment description and any report together. Ask which conclusions were established by examination and which remain unknown. The reference properties here describe a material; they are not measurements of a stone offered for sale.
If a description and report disagree, request clarification before making a decision. Photographs are useful for discussing appearance, but cannot authenticate a specimen. Keep care instructions with the item so that a jeweller or repairer can assess it before work begins.
Comparison and interpretation
To understand adularescence, look for a sheen that moves across the gem as the light or viewing direction changes. A still photograph may capture only one part of that appearance. Ask for a neutral-light video if the effect matters to your choice, while remembering that video still does not establish material identity. A trade colour name should be read alongside the actual feldspar identification. Compare moonstone with sunstone as different gem appearances in a broad family, rather than assuming that their light effects are interchangeable.
Choosing and documenting a piece
A smooth cabochon can make the moving sheen easy to observe, but its polished surface still needs protection. Ask about existing fractures and how the mounting supports the stone. Do not treat the mineral-family label as a guarantee that every item can be cleaned mechanically. Discuss a gentle cleaning method and the condition of the setting with a jeweller. A photograph with a blue reflection should not be described as proof of a particular source country. Keep any origin assertion separate from the visible appearance and identification evidence.
Before making a decision
For moonstone, ask the seller to identify the actual item, state what remains unknown and explain the scope of any report. Keep photographs, measurements and written disclosures together. If an answer matters to your decision, obtain it before commissioning a setting or arranging a repair.
Sources and further reading
- GIA Moonstone reference Checked 2026-10-16