Pure wool when burning, smoke, no flame blister, smelly, ash is glossy black solid, with a broken finger gently press it.

纯毛燃烧时无火焰，冒烟、起泡、有臭味，灰烬多呈有光泽的黑色固体，用手指轻轻一压就碎。

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It contains a lot of protein wool fibers from clothes, and smoke on fire, smell the scent, look like burning ashes, feather odor. If ashes with finger pressure are broken, it is pure wool.

真羊毛含有大量蛋白质，从衣衫上抽几根纤维点燃，闻一下气味，看一下灰烬，如有烧焦羽毛的气味，灰烬用手指一压即碎，就是纯羊毛；

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