The hand amulet was designed to sustain dexterity and manual activity1. The earliest are in carnelian, but other materials were used1. Position on mummies: wrist. Production covers all dynastic times

Carnelian H 1.6
Old Kingdom-First
Intermediate Period
MET #10.130.2358

Carnelian H 3.0 New Kingdom
Late Dynasty 18
Brooklyn Museum
#57.76.1

Turquoise/green glaze
H 1.1 Late Period
The Cleveland Museum
of Art Gift of the John
Huntington Art and
Polytechnic Trust 
#1914.793.5

References

1Andrews C. Amulets of ancient Egypt, 1994, p. 70
2in Plate I n°14 of Petrie W F M. Amulets, 1914 are two unretrievable hands side by side in blue glaze of Dynasty 6