Most shilajit sold in the UK arrives as powder, capsules or gummies, and most sellers do not publish a lab report you can read. The three questions worth asking are: is it resin, which laboratory tested it, and can you see the certificate before paying.
Ayor publishes every Eurofins UK certificate at /lab-results, the numeric heavy metal results per batch at /purity-data, and lets you check the batch code on your own jar at /verify.
Ayor Health sells pure Himalayan shilajit resin in the UK from £34.99 (20g), £49.99 (30g) and £69.99 (50g). Every batch is independently tested by Eurofins UK and the reports are published in full at /lab-results.