Online Mineral Buying Guide: Avoiding Fakes

How to Collect Minerals 4 分で読める

## The Challenge of Online Buying

Online mineral sales have exploded, but so have fakes, treatments, and misrepresentations. Understanding common deceptions protects your investment and ensures scientific accuracy in your collection.

## Common Fakes and Treatments

### Dyed Minerals

| Fake | Sold As | How to Spot |
|------|---------|------------|
| Dyed quartz | Citrine, amethyst | Uniform color, dye pooling in fractures |
| Dyed agate | Various trade names | Unnaturally vivid colors, bleed when wet |
| Dyed howlite | Turquoise | Too uniform, Mohs 3.5 vs turquoise 5–6 |
| Heat-treated amethyst | Citrine | Orange tint (natural citrine is pale yellow) |

### Manufactured Specimens

- **Bismuth crystals**: Genuinely lab-grown but often sold without disclosure
- **"Aura" quartz**: Metal-vapor coated quartz (titanium, gold) — not natural
- **Reconstituted turquoise**: Crushed turquoise bonded with resin
- **Glass sold as obsidian**: Andara glass, Goldstone (copper-flecked glass)

## Red Flags When Buying Online

### Seller Warning Signs

- No locality information provided
- Stock photos instead of actual specimen images
- Trade names without mineral species identification
- Prices that seem too good for the claimed species
- Healing crystal shops selling "rare" minerals

### Photo Warning Signs

- Oversaturated colors or heavy filtering
- No scale reference (coin, ruler)
- Single-angle photography hiding damage
- Identical background across hundreds of listings

## Verification Techniques

1. **Request additional photos**: Ask for images under different lighting and at multiple angles
2. **Ask for locality details**: Reputable sellers know their sources
3. **Cross-reference Mindat.org**: Verify that the claimed species occurs at the stated locality
4. **UV test upon receipt**: Many fakes fluoresce differently than natural counterparts
5. **Hardness test**: A steel knife (Mohs 6.5) quickly distinguishes dyed howlite (3.5) from genuine turquoise (5–6)

## Trusted Dealer Indicators

- Active presence on Mindat.org or mineral forums
- Membership in mineral dealer associations
- Return policy allowing independent verification
- Detailed locality and provenance documentation