Hadith 12:235
Abu Bakr narrated to us, he said: Abu Bakr ibn Ayyash narrated to us, from al-Shaybani, from al-Musayyab ibn Rafi’, who said: Alqama was asked about the *layt* (a sharp stone) with which one slaughters, and the *marwa* (flint/quartz). He said: "Everything that severs the jugular veins, except for the tooth and the nail."
حدثنا أبو بكر قال نا أبو بكر بن عياش عن الشيباني عن المسيب بن رافع قال سئل علقمة عن الليط يذبح بها والمروة فقال كل ما أفرى الأوداج إلا السن والظفر