The Land of Israel: Terumah, Ma'aser, Shmittah and Yovel, Kilayim: Mixtures of Fibers:
Does the Torah forbid all mixtures of fibers?
The "shatnez" mentioned in Lev.19:19 is defined more
precisely in Deut.22:11. The prohibition applies only
to mixtures of wool and linen; mixtures involving other
types of natural or synthetic fibers are permitted.
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