What is a Certificate of Analysis (and what it proves)?
A certificate of analysis (COA) is a laboratory report showing the results of tests on a sample of a product, usually a specific batch. For shilajit, it typically reports metals, microbiology and sometimes composition such as fulvic acid. A COA proves what the laboratory found in the sample it tested. It doesn’t, on its own, prove that your jar matches that sample, that the right tests were done, or that the product works.
Units on lab reports: ppm, ppb, mg/kg, per serving
Shilajit lab reports use several units. mg/kg and ppm are the same thing, as are µg/kg and ppb; 1 mg/kg equals 1,000 µg/kg. Per-serving results give an amount in a single serving, such as micrograms per serving. Microbiology uses colony-forming units per gram. GB supplement limits for metals are in mg/kg as sold, so per-serving figures need converting before you compare them.
What a complete Shilajit COA should contain (checklist)
A complete shilajit certificate of analysis should name an accredited laboratory, identify the batch and sample, give dates, and report numerical results with units and detection limits for lead, cadmium, mercury, arsenic and microbiology. Better reports add mycotoxins, pesticides, PAHs and, increasingly, inorganic arsenic and thallium, along with measurement uncertainty, remarks and a signature. Work through the checklist below each time you read a report.
Red flags in a Shilajit lab report
Red flags in a shilajit lab report include: no laboratory name or contact details, no batch number or one that doesn’t match your jar, results given as “pass” with no numbers, missing units or detection limits, no metals or microbiology, a very old date, and signs of editing. Some features that look odd at first, such as two results for one parameter, can have a simple explanation, so ask the brand before drawing conclusions.
Stability and shelf-life testing
Stability and shelf-life testing check how a product changes over time under defined storage conditions, so that a brand can set a best-before date with evidence. Tests may track moisture, appearance, microbial counts and selected components at intervals, either in real time or under accelerated conditions such as higher temperature. Little shilajit-specific stability data is published, so asking a brand how it supports its date is reasonable.
Our independent test programme
Best Shilajit UK plans to run an independent test programme in which we buy shilajit products anonymously from normal retail channels and send them to an accredited laboratory for the same contaminant panel. The programme has not yet published results. Until it does, our evaluations are based on brands’ own published laboratory reports, read critically, combined with first-hand checks such as purchase tests and matching a jar’s batch number to its report.
Lab methods: ICP-MS, ICP-OES, AAS, HPLC, FTIR, UV-Vis
Shilajit laboratory reports use several methods. ICP-MS and ICP-OES measure metals and minerals, atomic absorption spectroscopy (AAS) measures specific metals, HPLC separates and measures individual compounds, FTIR produces a chemical fingerprint used in identity testing, and UV-Vis spectroscopy is used in some composition tests. Each method answers a different question, so a report’s value depends on whether the right methods were used for the right tests.
Laboratories on UK brand COAs
UK shilajit brands use a range of laboratories, in the UK and abroad, for their certificates of analysis. What matters isn’t the laboratory’s country or name recognition but whether it is identifiable, accredited for the tests reported, and has tested the batch you are buying. Some brands publish reports from several laboratories, each covering different tests or samples, so it helps to know how to read them together.
Microbiological testing
Microbiological testing checks a shilajit batch for bacteria, yeasts and moulds, and for specific harmful organisms. A typical panel includes total viable count, yeasts and moulds, and tests for pathogens such as E. coli and Salmonella. Results are reported as colony-forming units per gram, or as absent in a stated sample size. Microbiology matters because shilajit is collected from the environment and dried, both stages where microbes can enter.
Mineral profile testing
Mineral profile testing measures the elements in shilajit, usually by ICP-MS or ICP-OES, reporting each as a concentration such as mg/kg. A profile can include common minerals such as iron, calcium and magnesium alongside toxic metals such as lead and arsenic. It is useful for describing a product and checking consistency, but the number of elements detected is not a quality measure, and amounts per serving are small.