This is a spindle.
It is from Osiris Temenos, Abydos. Spindles were used to handspin the linen thread for weaving. The spinner would roll the stick down the right thigh and then, holding the thread, leave the spindle to twist freely in the air. The spindle whorl gave the weight needed to twist. Painted tomb scenes show that Egyptian spinners (usually girls or young women) were able to manage two spindles at the same time. This is a spindle. It is made from stone. It is between 4,900 and 5,100 years old, dating to the 1st Dynasty (3100-2890 BCE) in the Early Dynastic Period.