Cashmere Electron Microscope Test

To ensure the high quality and value of cashmere, the fibers need to be measured in terms of scale density and thickness, pigmentation, diameter and other characteristics.

SGS has the experience and expertise to conduct the two commercially viable methods of measurement currently available: optical microscope and scanning electron microscope (SEM).

Cashmere identification with SEM

Using the SEM method allows our operatives to see, with high magnification, the surface of the fiber in detail. The high resolution (down to two nanometers) and large depth of field means that our experts can determine the surface characteristics more easily. It also allows them to measure topographical features such as scale height and density (the ratio of scale length to fiber diameter). While such measurements can be useful when objectively discriminating between fibers, it is worth noting that the SEM method does not reveal the fiber’s interior structure (or pigmentation).

We follow the relevant industry-standard methodology for measurement of composition by SEM, as set out by the International Wool and Textile Organization (IWTO-58). This uses the scale height to differentiate between wool (defined as having a scale height greater than 0.55 microns) and speciality fibers – including cashmere, mohair, camel, llama and alpaca.

Consistent, accurate measurements

Our operatives then identify the speciality fibers from other topological properties, such as scale shape, density and regularity of the fiber diameter – a somewhat subjective process. To maintain consistency and accuracy, we use industry-accepted measurement methods and provide our operatives with standardized training based on our traceable animal fibers library.

We have centralized the operation of our speciality animal fibers testing services in the UK. Approved by the Cashmere and Camel Hair Manufacturers Institute (CCMI), this facility is constantly involved in the development of: