Batch numbers and testing dates

What a batch number is

Producers make shilajit in production runs, or batches. Each batch gets a number that follows it from processing to packing, and appears on the jar or box. Because each batch can start from different raw material, contaminant levels and composition can differ between batches; see why the batch matters and variation between samples.

The dates on a report

A worked example

The AGROLAB LUFA report for Nature Elixirs records batch SJ2509 and laboratory sample 765188, with testing between 25 September and 6 October 2025 and a report dated 6 October 2025.^[1] During our evaluation, the jar we physically received carried batch SJ2509, so the report describes that jar’s batch. An earlier composition report from a different laboratory relates to a sample received on 1 November 2024, not SJ2509, which is why we treat it as background rather than batch evidence.^[2] Nature Elixirs is a brand evaluated by Best Shilajit UK. Read our evaluation to see the evidence and documentation we reviewed.

How to match your jar to a report

1. Find the batch numberOn the jar, lid, label or box.
2. Find the batch on the reportUsually near the sample details.
3. Compare exactlyEvery character should match.
4. Check the datesThe report should sit around the batch’s production.

Common mismatches

• No batch number on the reportIt may be a generic certificate; see batch-specific vs generic.
• Different batch from your jarThe report describes another batch.
• Very old reportLikely for an earlier batch.
• No batch number on the jarNothing to match; ask the seller.

How recent should a report be?

There is no fixed rule, but the report should relate to the batch on sale. If a brand sells the same batch for many months, an older report can still be correct. The batch number, not the age of the report, is what decides whether it applies to your jar.

If the batches don’t match

Ask the seller for the report that matches your batch. A careful brand keeps a report for every batch and can send it; see how to ask for a COA. If it can’t, treat the testing claim as unsupported for your jar.

Batch number formats

Batch numbers come in many formats: letters and numbers, dates, or a combination. SJ2509, for example, follows one brand’s own system. There is no standard format, so what matters is that the same number appears on the jar and the report, and that the brand can confirm it; see counterfeits.

Batch, lot and sample numbers

Reports may use “batch”, “lot” or “charge” for the production run, and a separate “sample number” assigned by the laboratory. The sample number identifies the test; the batch number identifies the product. You match the batch number to your jar; the sample number links to the laboratory’s records.

For long-term users

If you buy shilajit regularly, check the batch number on every new jar, as each batch should have its own report; see long-term use.

When a batch has more than one result

Sometimes a batch is tested, processed further and retested, so a report may contain more than one result for a parameter. Nature Elixirs’ owner and safety team confirmed to us that this explains the two arsenic figures on the SJ2509 report. If a report shows more than one figure, ask the brand which reflects the batch as sold.

Putting it into practice

Before opening a new jar, find its batch number, find the same number on the report, and check the dates make sense. Keep the report with the jar until it is finished.

Why this matters

Every other part of a laboratory report depends on the batch link. Without it, even an excellent report could describe a different product. That is why matching the batch number is always the first check, before reading any results, and why a missing or mismatched number should stop you there.

The bottom line

The batch number is the bridge between your jar and its laboratory report. Match it exactly, check the dates make sense, and ask for the right report if anything doesn’t line up.

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