Greasy Wool

SGS independently measures greasy (unwashed) wool to verify quality and quantity across different criteria. We operate to International Wool and Textile Organization (IWTO) standards wherever possible.

Our wool measurement services include certified tests for:

• Yield – determining the amounts of clean wool (woolbase) and vegetable matter contamination in a sample
• Mean fiber diameter – the average fineness of the wool (fiber thickness), which is a primary determinant of wool value 
• Color – measured as tristimulus values, but normally used to assess clean color brightness (Y value) and yellowness (Y-Z value)

We also perform additional tests, as required:

• Staple length and strength – we use the average staple length, strength and position of break to assess the performance of apparel wools in the worsted processing system 
• Bulk – this measures the fibers’ ability to fill space and also relates to resilience, which are important for applications such as carpets, futons and insulation 
• Fiber curvature – relates to bulk, compressibility and crimp and is cited as an influence on processing 
• Fiber diameter distribution – information about aspects of the diameter distribution may affect assessments of comfort and processing performance 
• Diameter-length profile – measuring the average diameter at increments along the length of wool staples may be important for managing sheep flocks and, in the future, may assist in predicting processing performance 
• Medullation – refers to the hollow fibers in wool and other animal fibers, which causes uneven dye uptake and adversely affects appearance in apparel wools (but may be desirable for some carpet types)

We can also test greasy wool samples using a variety of low-cost fleece testing methods that are specifically designed for animal selection purposes.

To verify the quality and quantity of greasy wool across a range of criteria, contact SGS now to ask about our independent testing services.