9.75" x 4.75"
Closest to the rim is Earth crust slurry from the mid-Atlantic Ridge, framed by gold leaf below which is sediment from the first core that proved the asteroid hit Earth about 65 million years ago known as the Cretaceous Tertiary Boundary or K-T Band. It's evident around the globe. Band near foot says, "Aeons from down deep and out far recycling. You are here now."
Shiny brown is glaze made from wood ash, clay, yellow ochre and some Red Sea sediment.