Physical Properties of Wool

1. Wool is made of Protein and Oils

Keratin is the primary protein in wool, the same as the proteins found in our fingernails and hair. Much like our skin, sheep secrete an oil - Lanolin - that coats the fibers. These oils (lipids) are generally not hospitable for bacterial growth.

2. Keratin is Hygroscopic

Wool fibers are hygroscopic, meaning they have the ability to absorb moisture vapor into the fiber. Merino wool can absorb about 36% of its weight in moisture, while still being able to wick liquid sweat, unlike cotton. This creates a very dry environment that is inhospitable to bacterial growth.

3. Scales, Fibrils and Washable Wool

Merino yarns have a unique surface structure that features "scales" which allows wool to be felted and turned into yarns. It's also why regular wool shrinks. These scales give wool a matte appearance - like a stealth aircraft - they deflect light in multiple directions.

4. Size and Softness

A key determining aspect of softness is the size of the fiber. Finer fibers are less likely to exert a concentrated force on our skin's surface receptors. We usually use "Extra-Fine" Merino for a balance of both softness and durability.

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