As of November 2021 there is a separate entry for the tweed colors. Please link to that for the yarn that isn’t 100% wool.

Yarn weight entered is based on MPG & gauge from ball band. Users should be aware when substituting yarns that in reality Fishermen’s Wool is a light worsted weight.

Per the Lion Brand website, Birch Tweed, col #202, is not 100% wool and skein size is different. It is listed separately due to the difference in fiber content.

202: 6 oz (170 g), 348 yards (318 m) 78% Pure Virgin Wool, 13% Acrylic, 9% Rayon

Other colors listed on Ravelry have been hand-dyed.

From Lionbrand.com:
Our classic Fishermen’s Wool is made of undyed pure virgin wool with natural lanolin oil. Soft, warm, and naturally water resistant, it’s ideal for ski-wear and fisherman sweaters, hats, scarves, and more. Fishermen’s Wool also felts beautifully for dense slippers, strong bags, and textural home decor projects. Plus its generous size and natural shades make it perfect for dyeing.

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