A Certificate of Analysis (COA) is the most important document in the shilajit market — but most buyers don't know what to look for, and most brands count on that. This guide cuts through the jargon and shows you exactly what to find, what numbers matter, and what red flags mean a product shouldn't be in your cart.
By the end, you'll be able to evaluate any shilajit COA in under five minutes with confidence.
What Is a COA and Why Does It Matter?
A Certificate of Analysis is a document issued by an independent, accredited testing laboratory that details the chemical composition and safety profile of a product. For shilajit, it is the only objective, third-party mechanism for verifying what is actually in the jar.
Without a published COA, any claim a brand makes about fulvic acid content, purity, or heavy metal safety is completely unverifiable. A brand that does not publish COAs may have a genuinely good product — or they may not. The point is you have no way to distinguish the two.
This matters because the shilajit supplement market has documented quality issues. Studies evaluating commercially available shilajit products have found wide variation in active compound concentrations and, in some cases, contaminant levels that exceed safe thresholds. A COA from a competent lab is the only reliable safeguard available to consumers.
See our guide on how to spot fake shilajit for broader quality signals beyond the lab document.
How to Find a Brand's COA
A legitimate brand publishes its COA prominently. Check the brand's website first: the product page, a dedicated "Lab Results" or "Third-Party Testing" section, or the FAQ. A brand that makes you hunt for it is a yellow flag. One that says "available upon request" but never delivers is a red flag.
Green Flag
PDF download directly linked from the product page or a dedicated "Lab Results" tab. Shows current batch date.
Yellow Flag
COA is accessible but buried in the FAQ or takes more than two clicks. May be an older document not specific to current batches.
Red Flag
"COA available upon request" that is never sent. No lab name visible. Generic "third-party tested" badge with no linked document.
Fulvic Acid Percentage — The Most Important Number
Fulvic acid is shilajit's primary bioactive compound. It is a naturally occurring organic acid that research suggests facilitates mineral absorption, acts as an antioxidant, and may support cellular energy processes. A 2016 study published in the Journal of Alzheimer's Disease identified fulvic acid as one of shilajit's key active components due to its role in mitochondrial function and its interaction with tau proteins.
On a COA, fulvic acid percentage is reported as a dry weight percentage of the total sample. Here is how to interpret the number:
| Fulvic Acid % | Quality Tier | What It Means |
|---|---|---|
| Below 20% | Low | Sub-standard; likely diluted, adulterated, or poor sourcing |
| 20–40% | Marginal | Below our recommended minimum for premium purchases |
| 40–60% | Acceptable | Meets basic quality threshold; adequate for most buyers |
| 60–80% | Good | Solidly above average; Pure Himalayan reports 60% at the lower edge of this band |
| 80%+ | Premium | Top tier; Black Lotus reports 85%+ with COA verification |
On a COA, look for a line labeled "Fulvic Acid," "Fulvic Acid Content," or "Humic/Fulvic Fraction" with a percentage value. The test method (e.g., UV-Vis spectrophotometry or volumetric titration) should also be listed. If no method is cited, the number is unverifiable.
Heavy Metals Panel — What Safe Limits Look Like
Because shilajit is a mineral-dense geological material, it naturally accumulates trace metals during formation. Most of these are beneficial minerals — magnesium, zinc, iron, copper. However, lead, mercury, arsenic, and cadmium can also be present and are toxic above certain thresholds. A legitimate COA tests for all four.
The table below shows the FDA/USP dietary supplement safety limits for each heavy metal. A trustworthy COA shows the actual measured value, not just "PASS." Seeing actual numbers — especially values reported as ND (Not Detected) — is the most reassuring outcome.
| Heavy Metal | Symbol | Safe Limit (ppm) | What ND Means |
|---|---|---|---|
| Lead | Pb | <10 ppm | Not Detected below instrument threshold — best outcome |
| Mercury | Hg | <3 ppm | ND is ideal; any detectable Hg should be well below limit |
| Arsenic | As | <15 ppm | ND common in high-altitude sources; elevated As is a concern |
| Cadmium | Cd | <5 ppm | ND preferred; cadmium accumulates in kidneys over time |
Limits per FDA dietary supplement guidance and USP general chapter standards. Always verify against the COA for the specific batch you receive.
If a COA shows only "PASS" without numerical values, that is a yellow flag. You cannot verify whether "PASS" means 0.001 ppm or 9.9 ppm (both technically below the limit). Actual numbers let you make informed decisions, especially for long-term daily use. See our detailed guide on shilajit heavy metals safety for a deeper analysis.
Microbial Testing
Microbial testing verifies that the product does not contain harmful bacteria, yeast, or mold at unsafe concentrations. For a raw resin product that will be consumed daily, this section of the COA matters more than many buyers realize.
Look for these specific results on a microbial panel:
Total Aerobic Plate Count (TAPC)
Overall bacterial load. Should be within USP dietary supplement limits (typically <10,000 CFU/g for non-sterile preparations).
Yeast and Mold
Should be within USP limits (<100 CFU/g for some supplement categories). High yeast/mold count indicates poor storage or processing conditions.
E. coli
Should be 'Not Detected' (ND). Any detectable E. coli is a fail condition.
Salmonella
Should be 'Not Detected' in the full sample tested. Absence is required; presence disqualifies the product.
Staphylococcus aureus
Should be 'Not Detected' or below the limit of detection. A pathogenic strain that can cause illness at relatively low concentrations.
What Lab Accreditation Actually Means
Not all labs are equal. "Third-party tested" is a marketing phrase, not an accreditation. A lab calling itself "independent" has no required standard of competence. This is why lab accreditation — and specifically which accreditation — matters.
ISO/IEC 17025 is the gold standard. Labs with this accreditation have been externally assessed by a recognized accreditation body (such as A2LA in the US, UKAS in the UK, or any ILAC network member) for technical competence, calibrated equipment, validated methods, and quality management. Pure Himalayan Shilajit's COAs come from an ISO/IEC 17025 accredited lab — a specific, verifiable credential.
To verify independently: take the lab name from the COA and search for it in your country's accreditation body database. Legitimate ISO/IEC 17025 labs are publicly listed with their scope of accreditation. If the lab named on a COA has no public website, no searchable listing, or no identifiable contact information, that is a serious red flag.
Green Flags vs Red Flags on a COA
| What You See | Signal | What It Means |
|---|---|---|
| Fulvic acid % ≥ 40% with test method cited | Green | Meaningful, verifiable bioactive content claim |
| Actual heavy metal values (not just PASS) | Green | Transparent — you can verify the numbers yourself |
| ISO/IEC 17025 accredited lab named | Green | Lab competence has been externally verified |
| Batch/lot number on COA matches product | Green | COA applies to what you're actually buying |
| Pathogenic strains (E.coli, Salmonella) = ND | Green | Microbially safe for consumption |
| Only 'PASS' shown — no numeric values | Yellow | Cannot verify whether values are barely passing or well below limits |
| No lab name or lab is unverifiable | Red | COA provenance cannot be confirmed |
| Fulvic acid % not reported | Red | Primary bioactive compound unverified |
| COA dated more than 2 years ago | Red | May not reflect current formulation or sourcing |
| Heavy metals section absent entirely | Red | Safety profile unverified for a mineral-dense product |
The Brands with the Strongest COA Transparency in Our Database
Of the brands we've evaluated, two consistently meet our full COA transparency criteria: published fulvic acid percentages, actual heavy metal values, named and verifiable labs, and current batch documentation.
Black Lotus Shilajit
Pure Himalayan Shilajit
See the full comparison on our brand comparison page.
What to Do If a Brand Won't Show You a COA
Move on. This is the simplest and most practical advice. The shilajit market has enough verified, COA-transparent options that there is no reason to take a quality risk on a brand that refuses basic transparency.
If a brand says their COA is "proprietary" or "competitive information" — that is not how lab testing works. A COA certifies what is in the product; it does not expose trade secrets. The only reason a brand avoids publishing a COA is that the results either don't exist or wouldn't support their marketing claims.
For a broader guide to identifying low-quality products, see our post on how to spot fake shilajit.
Skip the Research — Shop COA-Verified Brands Directly
Both brands below publish complete COAs: fulvic acid percentages, actual heavy metal values, and named, verifiable labs. No guesswork required.
Related Guides
85%+ fulvic acid · Third-party COA · Cold-processed · Free shipping — S-tier resin at $36.99.
- 85%+ fulvic acid — verified by ISO-accredited third-party lab
- ~150mg fulvic acid per 175mg serving
- Full heavy metals panel: all below FDA action levels
- Cold-process purification preserves bioactive compounds
- Himalayan source above 14,000 feet elevation
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Frequently asked questions
What is a shilajit COA?
A COA (Certificate of Analysis) is a document issued by an independent testing laboratory that details the chemical composition and safety profile of a supplement. For shilajit, a COA typically reports fulvic acid percentage, heavy metal concentrations (lead, mercury, arsenic, cadmium), microbial counts, and purity data. It is the primary objective document for verifying what is actually in a shilajit product.
What fulvic acid percentage is good in shilajit?
We use four tiers: below 20% is low quality; 40–60% is acceptable; 60–80% is good; 80%+ is premium. Pure Himalayan Shilajit reports 60% fulvic acid; Black Lotus reports 85%+. Both clear our recommended minimum of 40%. Anything below 20% from an unverified source should be treated with skepticism, especially if no COA is published.
Are heavy metals in shilajit dangerous?
Shilajit is a mineral-rich substance and naturally contains trace minerals, including metals. The question is whether those metals are within safe consumption limits. The key thresholds are: Lead under 10 ppm, Mercury under 3 ppm, Arsenic under 15 ppm, Cadmium under 5 ppm (per FDA/USP dietary supplement guidelines). A trustworthy COA shows actual measured values — not just 'PASS' — so you can confirm the numbers are below these limits.
What does ISO/IEC 17025 mean on a shilajit COA?
ISO/IEC 17025 is the international accreditation standard for testing and calibration laboratories. A lab holding this accreditation has been assessed by an external accreditation body for technical competence, validated test methods, and quality management. It is a stronger credentialing claim than 'third-party tested,' which carries no specific accreditation requirement. Pure Himalayan Shilajit uses an ISO/IEC 17025 accredited lab for their COAs.
Can I trust Amazon shilajit COAs?
Amazon shilajit listings vary widely. Some legitimate brands sell through Amazon and publish real COAs; many do not. The risk with Amazon is that product listings can be commingled (mixed with other sellers' inventory) and COAs may be outdated or not specific to the batch you receive. For COA-verified shilajit, we recommend purchasing directly from the brand's own website, where you can verify the COA applies to current production lots.