Camlet is a plain woven fabric. Some camlets were made of goat, some were partly silk or linen. The most expensive were silk and camel-hair, or wool and goat's hair. Presumably it was originally made of camel hair. I have seen a reference to the Arabic seil el kemel, which is the Angora goat.
Very difficult to know exactly what was in it! Gentleman fly-dressers will have obtained the best they could, so I suppose it may well have been camel hair? Anyway, mohair is a perfect "substitute" !
camleteen, camletine = imitation camlet of hair and worsted.
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