Leather

Leather is tanned animal hide — no plastic in the material itself, and a well-made leather item can last decades and be repaired repeatedly.

Two honest caveats: tanning chemistry varies widely (vegetable tanning is the traditional low-chemistry route), and some finished leathers carry thin polymer top-coats. “Genuine leather” at suspiciously low prices is often bonded leather — scraps glued with polyurethane.

Leather scores 0/100. Faux, vegan, PU, and bonded leathers are different materials and score 90–100 — the label wording decides which page you are on.

The same weight applies everywhere: a product's score is the percentage-weighted plastic share of its listed fiber composition, and every weight is public.