Overview
ISO 11457:2018 specifies guidance for the grading of wet blue goat and sheep skins based on defects. It defines grading principles, terminology and visual criteria used to evaluate chrome‑tanned intermediate hides (wet blue) for quality, cutting value and suitability for different end uses. The standard targets grading by visible grain‑side defects and uses schematic skin areas (figures) to identify prime portions.
Key Topics
- Scope and terms
- Defines wet blue, and defect terms such as scabies and pocca (warble/warble marks).
- No normative references; prepared by ISO/TC 120 (Leather).
- Presentation
- Requires well‑trimmed wet blue goat and sheep skins (neck, fore/hind legs, tail).
- Grading criteria
- Grading is based on three main checks: cutting value, defect and grain texture.
- Grading uses schematic areas to identify where defects are acceptable or disqualifying.
- Goat skin grades (I–V)
- Grade I: defects ≤ 10% of total area; fine smooth grain; prime clear portions.
- Grade II: defects 10–20%; minor healed defects allowed in certain areas.
- Grade III: defects 20–40%; acceptable minor pocca, vein marks in non‑prime areas.
- Grade IV: defects up to 70%; scattered pocca, pinholes, open defects in multiple areas.
- Grade V: defects up to 85%; thin/empty skin, heavy drawn grain, open defects.
- Sheep skin grades (A–E)
- Grade A: defects ≤ 10%; no rib/blood vessel marks or drawn grain.
- Grade B: defects 10–20%; limited scattered defects and light flay cuts in non‑prime areas.
- Grade C: defects 20–40%; coarse grain, scabies, pinholes, light rib marks.
- Grade D: defects ≤ 60%; some open defects across non‑prime portions.
- Grade E: defects ≤ 80%; open defects across most of the skin except minimal cuttable area.
- Remarks
- Skin area and substance, and final selection, depend on buyer‑seller contract and intended end product (shoes, garments, gloves, leather goods).
- Grading focuses on grain‑side defects; suede or heel‑grip manufacturers may accept lower grades if flesh side is clean.
Applications
ISO 11457 is used by:
- Leather tanneries for sorting and pricing wet blue goat and sheep skins.
- Quality control teams to apply consistent defect‑based grading.
- Buyers, traders and spec writers for procurement contracts and commercial grading terms.
- Product developers selecting skins for shoes, garments, gloves, suedes and other leather goods where cutting yield and defect distribution matter.
Keywords: ISO 11457, leather grading, wet blue goat skins, wet blue sheep skins, defect grading, cutting value, grain texture.
Related Standards
- Relevant to other ISO leather standards and guidance produced by ISO/TC 120 (Leather). For purchaser or laboratory conformity details consult national standards bodies or the ISO catalogue.
