Leather Defects: How to Recognize Faults From the Farm, the Tannery and the Finish

Back to leather finishes, textures, and natural markings

A leather defect is damage that weakens the material or that should have been caught at grading; a healed scar or growth wrinkle is a natural mark, not a defect. Defects start at three points before tanning: on the live animal, at slaughter and after slaughter. More are added in the tannery and the finish.

Common leather defects at a glance

Natural mark or defect? The rule tanneries use

One tannery guide puts it simply: a natural mark is proof of genuine full grain, while a defect weakens the leather or should have been graded out. Healed scars, insect bites, stretch marks and growth wrinkles sit on the natural side of that line.

Scars are the grey area. One UK maker says scarring leaves the leather's structure intact, while a US maker says deep or numerous scars can weaken a hide. Read both views in scars and scarring on leather, and the full list of harmless features in common marks and natural features on leather.

Defects from the live animal

A 2015 study at one Ethiopian tannery found scratches on 64.2% of the skins and hides it examined, cockle on 32.8%, wounds or scars on 12.6% and pox or lumpy skin lesions on 6.1%. Branding marks (2.3%) and tick bites (1.5%) were less common.

These figures describe one tannery and one region. They show which faults are common, not how often they appear in leather you buy.

Defects from slaughter and curing

Flay cuts, holes, poor pattern and vein marks are made at slaughter. A US tannery's glossary calls butcher cuts deep cuts made when the hide is removed at the packing house.

Sources disagree on veins. The Ethiopian study counts vein marks as a slaughter defect, while a tannery guide lists veins as a natural mark of the live animal.

After slaughter come grain cracks (14.9% in the study), hide beetle damage (8%), heat or putrefaction damage (3.7%) and machine-induced damage (0.5%). Hair slip and salt stains are on the same tannery's defect list.

Defects made in the tannery and the finish

A tannery guide to defects and natural marks names a straight machine stripe from a setting or shaving roller, drawn grain, chrome or dye stains and uneven thickness as process faults. Loose grain that cracks when folded is on the same list.

Finish faults show on the surface: color rub-off (tested to ISO 11640), whitening or peeling of a coated finish, and pinholes. Pure aniline teals, blues and greens are the colors most prone to rub-off. Peeling has its own page: does top-grain leather peel?.

How defects affect grade and price

There is no single grading standard that all tanneries share, and A-D or #1-#4 grades measure cosmetic yield, not strength. At one US tannery, every grade goes through the same tan yards, so a lower grade means more marks and less usable area, not a weaker tannage.

For example, one brand typically costs about a square foot of cutting area. See leather grades explained for how the grades are set.

How to check a hide or a finished piece

1. Look at the whole side before cutting, and raise defects with photos of the full side, not a close-up.
2. Agree the tolerance in writing if you buy hides in bulk.
3. Fold the grain inward. Loose grain cracks when folded.
4. Check the belly edges. Belly leather is looser and wrinkled and is meant for linings or hidden panels.
5. Ask for test values: ISO 11640 (rub fastness), ISO 11644 (finish adhesion), ISO 5402-1 (flex) and ISO 3379 (grain distension).

Leatherworker Tanner Leatherstein unrolls whole hides and points out neck scratches, bite marks, loose flanks, holes and deep flaying cuts, then judges how much clean cutting area is left. Watch how he separates marks he can cut around from areas he cannot use.

Defects that come with age

Old vegetable-tanned leather kept in humid, polluted or hot conditions can suffer red rot, a powdering of the surface with structural weakness. The damage cannot be reversed.

One leather goods maker lists very dry air, direct sun and heat among the causes of stiff leather. How finish and softness interact is covered in what makes leather soft.

Hide choice in a made-to-order jacket

Each product page in the Leather Collection men's leather jackets range names the animal, but not a grain grade. If marks or defects matter to you, ask how panels are selected before ordering.

FAQ

How can you tell if something is high quality leather?

Check for real defects such as cracking grain, rub-off or peeling rather than natural marks. Then look at the layer and finish; see types of finished leather and how they differ.

What deteriorates leather?

For vegetable-tanned leather, prolonged high humidity, pollution and high temperature can cause red rot. One maker also names very dry air, direct sun and heat as causes of stiffness.