Ibn Abi Zayd: Al-Risala (the Epistle) (d996), from Qayrawan in Tunisia.
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Taken from: http://www.muwatta.com/ebooks/english/risala_ibn_abi_zayd_salutations.pdf
29.6g Feathers, horns, teeth, hooves, tusks
You cannot use feathers from birds which are carrion or the horns, hooves and teeth of carrion animals. It is disliked to use elephant tusks although there is a difference of opinion about this
40.22f Hair and wool
The wool and hair of carrion are used as well as what is removed from them while alive. We prefer that it be washed. One does not use its feathers, horns, claws or teeth. It is disliked to use the tusks of elephants.
43.16 Trading abroad
It is disliked to trade in the land of the enemy or the land of the blacks.
The Holy Prophet said, Travel is a portion of punishment.
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