hewn stone. The other eight (Ezekiel 40:41) were probably of wood.
Related Commentaries of Ezekiel 40:42
Ezekiel 40:42
42 And the four tables were of hewn stone for the burnt offering, of a cubit and an half long, and a cubit and an half broad, and one cubit high: whereupon also they laid the instruments wherewith they slew the burnt offering and the sacrifice.