Crystal Lab Reports: How We Test Every Stone
Crystal Lab Reports: How We Test Every Stone
A transparent look at the exact tests, parameters, and rejection criteria our gemology team applies to every crystal before it enters the Evashu catalogue.
At Evashu, "tested" isn't a marketing word — it's a documented process. Every crystal that enters our sourcing pipeline is assessed against measurable gemological parameters before it earns a place in our inventory. This page explains the exact tests we run, what each parameter means, and how you can use this information to verify any stone yourself.
This testing process is part of our broader 7-step sourcing and certification system, overseen by our gemology and quality team.
The 6 Gemological Tests We Run
These are the core scientific parameters our team evaluates for every batch of raw material. Each test has a defined pass/fail range based on published gemological reference data for the specific mineral.
Mohs Hardness Test
We verify the scratch resistance of every stone against the Mohs scale. This is the single most reliable field test for mineral identification — a real Amethyst must register 7 on the Mohs scale, while glass (often sold as crystal) sits at 5.5. Any stone that falls outside its expected hardness range is flagged for further testing or rejected outright.
Specific Gravity Measurement
Specific gravity (density relative to water) is a fingerprint for each mineral. We weigh each stone in air and in water to calculate its SG value. For example, genuine Pyrite has an SG of approximately 5.0 — significantly heavier than most imitations. A stone with the wrong SG for its claimed mineral identity fails immediately.
Refractive Index Check
Using a refractometer, we measure how light bends as it passes through the stone. Every mineral has a characteristic RI range — genuine Labradorite shows 1.559–1.568, while glass shows a flat 1.50. This test catches high-quality glass imitations that might pass visual inspection alone.
Visual & Loupe Inspection
Under 10x magnification, our team examines the stone's internal structure — looking for natural inclusions, growth patterns, and fracture characteristics that confirm natural origin. Synthetic and lab-grown stones typically show uniform, bubble-free interiors or curved growth lines that natural minerals don't produce. We also check for surface evidence of dye application, coating, or resin filling.
UV Fluorescence Test
Certain minerals exhibit characteristic fluorescence under ultraviolet light. We use both long-wave and short-wave UV to verify identity — for instance, natural Selenite fluoresces a distinctive blue-white, while Fluorite (the mineral fluorescence was named after) shows strong violet-blue. Absence of expected fluorescence or presence of unexpected fluorescence triggers further investigation.
Crystal Structure Verification
Natural minerals form in specific crystal systems — Clear Quartz is hexagonal, Garnet is cubic, Moonstone is monoclinic. We examine cleavage planes, fracture patterns, and crystal habit to confirm the stone matches its claimed mineral species. Glass and synthetic materials show conchoidal fracture with no crystallographic direction — a dead giveaway under magnification.
Test Parameters by Stone
Below are the gemological reference values our team uses for our most popular crystals. These are the same values published in standard gemological references — if your stone doesn't match these ranges, it may not be genuine.
| Crystal | Mohs | Specific Gravity | Refractive Index | Crystal System |
|---|---|---|---|---|
| Amethyst | 7 | 2.63–2.65 | 1.544–1.553 | Trigonal |
| Pyrite | 6–6.5 | 4.95–5.10 | Opaque | Cubic |
| Rose Quartz | 7 | 2.63–2.65 | 1.544–1.553 | Trigonal |
| Tiger Eye | 6.5–7 | 2.64–2.71 | 1.544–1.553 | Trigonal |
| Labradorite | 6–6.5 | 2.69–2.72 | 1.559–1.568 | Triclinic |
| Citrine | 7 | 2.63–2.65 | 1.544–1.553 | Trigonal |
| Black Tourmaline | 7–7.5 | 3.02–3.26 | 1.624–1.644 | Trigonal |
| Moonstone | 6–6.5 | 2.55–2.63 | 1.518–1.526 | Monoclinic |
| Obsidian | 5–5.5 | 2.35–2.60 | 1.45–1.55 | Amorphous |
| Green Aventurine | 6.5–7 | 2.64–2.69 | 1.544–1.553 | Trigonal |
| Lapis Lazuli | 5–6 | 2.70–2.90 | 1.50 (aggregate) | Cubic (Lazurite) |
| Carnelian | 6.5–7 | 2.59–2.61 | 1.530–1.539 | Trigonal |
How to Use This Table
If you already own a crystal and want to verify it, check its Mohs hardness first — it's the easiest test to do at home. A genuine Amethyst (Mohs 7) should scratch glass (5.5) easily. If it can't, it's likely glass or a softer imitation. For detailed stone-by-stone identification guidance, browse our Crystal Glossary A-Z.
The Full 12-Point QC Checklist
Beyond the 6 gemological tests, every finished product passes through 6 additional quality parameters before being added to our product catalogue:
- Stone Authenticity — Passed all 6 gemological tests above
- Colour Fidelity — Stone colour matches listing photos within natural variation range (we photograph under standardised daylight conditions)
- Bead Count Accuracy — For bracelets, exact bead count matches product specification
- Elastic Strength — Bracelet elastic stress-tested for stretch resistance and recovery
- Structural Integrity — For trees, pyramids, and figurines, bonding points and base stability are load-tested
- Weight Verification — Product weight measured and compared against expected range for the stone type and size
- Surface Defect Screening — Visual inspection for chips, cracks, uneven polish, or manufacturing defects
- Bore Alignment — For beaded products, bore holes are checked for centring and smoothness to prevent thread abrasion
- Symmetry Check — Bead diameter consistency across the strand (±0.5mm tolerance)
- Finish Quality — Surface polish graded for smoothness and lustre appropriate to the stone type
- Charging Confirmation — Reiki energy charging completed and batch charging date documented
- Packaging Integrity — Product correctly packaged in protective box with foam inserts to prevent transit damage
Automatic Rejection Criteria
Any stone or finished product exhibiting the following is immediately pulled from inventory with no exceptions:
- Dye evidence — Colour pooling in fractures, colour transfer on cotton swab, or acetone sensitivity
- Resin filling — Surface bubbles, sticky residue under heat, or unnaturally uniform transparency in typically included stones
- Heat treatment (undisclosed) — Crackle patterns, colour zoning inconsistencies, or stress halos not natural to the mineral. Note: if a stone is standardly heat-treated in the trade (certain Carnelian), we disclose this on the product page
- Synthetic/lab-grown origin — Curved striae, gas bubbles, or absence of natural inclusions characteristic of the mineral species
- Misidentification — Stone does not match claimed mineral identity across two or more test parameters (e.g., dyed Howlite sold as Turquoise, glass sold as Obsidian)
- Structural failure — Bracelet elastic fails stress test, tree wire bonding fails load test, or pyramid base is unstable
Common Fakes We Catch
The Indian crystal market has well-known substitution patterns. Here are the most common fakes our testing catches — and why they fail:
Glass as "Obsidian"
Black glass is widely sold as Obsidian. While both are amorphous, glass shows perfect conchoidal fracture with no flow banding, and its SG (2.2–2.5) often falls below natural Obsidian's range.
Dyed Howlite as "Turquoise"
White Howlite dyed blue is the most common turquoise imitation globally. Cotton swab with acetone lifts dye immediately. Under magnification, dye pooling is visible in surface pores and fractures.
Heat-Treated Amethyst as "Citrine"
Baked Amethyst is sold as natural Citrine across the market. Natural Citrine shows pale, smoky-yellow colour with even distribution. Heat-treated stones show burnt-orange tips with white bases and stress crackle patterns.
Dyed Agate as "Carnelian"
Genuine Carnelian shows colour variation when backlit. Dyed agate shows uniform colour with no banding, and acetone on a cotton swab lifts the surface dye. Some trade-standard heat treatment is accepted and disclosed.
Resin-Filled Quartz as "Natural"
Cracked quartz filled with resin to improve clarity. Under gentle heat, resin becomes sticky. Under magnification, bubbles appear along fracture planes. Mohs test shows inconsistent hardness at filled vs unfilled areas.
Glass as "Rose Quartz"
Pink glass is sold as Rose Quartz. Glass (Mohs 5.5) won't scratch genuine quartz (Mohs 7), RI reads flat ~1.50 instead of 1.544–1.553, and loupe shows gas bubbles instead of natural rutile inclusions.
How to Request a Lab Report
For premium and high-value stones — including Labradorite, natural Citrine, and Moonstone — you can request a third-party gemological lab report at the time of purchase or after delivery.
What's included in a lab report?
- Mineral species identification and variety name
- Weight in carats and grams
- Measured Mohs hardness range
- Specific gravity value
- Refractive index reading
- Treatment disclosure (natural, heated, untreated)
- Origin assessment (where determinable)
- Photographic documentation of the tested specimen
How to request
Email Support@Evashu.in with your order number and specify which product you'd like a lab report for. Lab reports are sourced from independent third-party gemological laboratories — not generated internally — to ensure objectivity. Additional charges may apply depending on the stone and report type.
Frequently Asked Questions
Can I test my crystal at home?
Yes — the Mohs hardness test is the easiest to do at home. Attempt to scratch a glass plate (Mohs 5.5) with your stone. A genuine Quartz-family crystal (Amethyst, Citrine, Rose Quartz, Tiger Eye) at Mohs 7 should scratch glass easily. If it can't, it's likely not genuine quartz. For detailed identification tips stone by stone, see our Crystal Glossary A-Z.
Do all your products come with lab reports?
No. Lab reports are available on request for premium stones. All products undergo our internal 12-point QC process, but third-party lab reports involve external laboratory fees and are offered as an optional add-on for customers who want independent verification.
What if my crystal fails a home test?
Contact us at Support@Evashu.in with your order number, test results, and photos. If a product fails to match its listed mineral specifications, our return policy fully covers it. We take authenticity issues seriously — our entire brand is built on the promise that every stone is genuine.
How is this different from your sourcing page?
Our Crystal Sourcing & Certification page covers the full journey from mine to doorstep — including supplier vetting, ethical sourcing, craftsmanship, and packaging. This page focuses specifically on the scientific testing and quality control parameters. Together, they document the complete process.
Every Crystal. Every Test. Every Time.
Shop knowing that every stone has passed our full testing process.
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