The precise role of these plaques is unknown1. They might be funerary urn labels or stamp seals (see the descriptions of the World Museum Liverpool). Both plaques were found in Meroe, Kushite Dynasty 25

Eroded glaze with outer cartouches
with ribbed leaf pattern and the
central one hieroglyphs. Handle broken
in the back H 7.2, W 5.7, T 1.1
World Museum Liverpool #49.47.853

Green glaze, outer cartouches with
ankhs and the central cartouche
containing a ram’s head with sun disc above a rosette
Top broken H 7.0, W 6.5, T 1.1
World Museum Liverpool #49.47.851

References

1None, Unpublished amulets