Tanned leather
can turn intoan allergen.

Not in itself, and it would be alarmist to suggest otherwise, since the great majority of leather in the world is chrome-tanned. The tanning uses chromium III, which is not restricted on skin-contact grounds. The issue is a conversion: under heat, an unfavourable pH, certain fats or prolonged storage, a small proportion of chromium III can oxidise into chromium VI, which is a skin sensitiser. That is why the restriction exists and why it is set very low, at three milligrams per kilogram, which is three parts per million. Vegetable-tanned leather avoids the question entirely but behaves and ages differently, and is not better for every purpose.

A delayed eczematous reaction where the leather touched the skin, typically appearing a day or two after exposure rather than immediately. The feature that matters is permanence: once someone is sensitised to chromium, they remain sensitised, and subsequent contact with far smaller amounts can set off a reaction. That is why the limit is a threshold for placing goods on the market rather than a warning to be printed on a label. If you already react to chrome-tanned leather, say so before ordering, and we will discuss materials rather than talk you out of it.

Because a certificate has a date on it and chromium VI can form after the test. A certificate issued at the tannery records the condition of that leather on that day; by the time a hide has crossed a continent, sat in a warehouse through a hot summer and been cut, the result is older than it looks. We therefore treat the age of a test result as part of the information rather than as a formality, and we will tell you what was tested and when rather than waving a document. It is a small distinction that makes a genuine difference to what the paperwork is worth.

Yes, and the one worth knowing about alongside chromium is azo dyes. Azocolourants capable of releasing certain aromatic amines are restricted in textile and leather articles which may come into contact with human skin, because those amines are the concern rather than the dye itself. It applies to the same category of goods and for related reasons. Dyes are a less frequent problem than chromium in practice, but they belong on the same list of questions to put to a supplier.

No, and this answer exists because the standardised wording of one of our registered activity codes mentions saddlery and harness. We offer no saddle fitting service and we do not hold ourselves out as qualified saddle fitters. It is worth knowing, if you are looking for one, that saddle fitting is not regulated by statute in the United Kingdom: qualifications exist but they are voluntary, so a claim of competence is the only signal a buyer gets. Verify it with the body that awarded it rather than taking a website's word, including ours.

Almost certainly not. Leather stretches where it is stressed, darkens where it is handled and marks where it has been, and no two hides begin identical. That is the material doing what the material does, and it is the reason a leather garment looks better after three years than it did new. A fault is something else: a seam failing, a lining tearing from its stitching, hardware breaking, finish lifting in sheets. Bring it in and we will tell you which it is, and if it is a fault your statutory remedies are not affected by anything on this page.