what material is used to create the faces and limbs
Shabtis, also sometimes called ushebtis or shawabtis.
King Tut had a male parrot and a female greyhound. So count 'em, two (:
Shabtis, also called ushebtis or shawabtis. They helped with manual tasks in the afterlife. They were craved either from wood or stone.
Shawabtis (or ushabtis or shabtis) - from ancient Egyptian wshb, to answer- are thought to have been servants for the dead person in the afterlife, in exactly the same way that they had real servants in this life.They only represented the "spirit servant" who would answer whenever the dead person's spirit called them, so they did not need to be full-size; most are only a few inches tall (perhaps in the range 3 to 7 inches, 7.5 to 18 cms).The link below takes you to a display of shawabtis in the British Museum collection:
It is called a ushabti, also spelled as shabti.