These images show the outcome of my slip casting and grog tests. I have revealed the grog of one, yet I have lost the lines. I also tried draping a sponge on the surface to add a very fine texture to the surface.
After the bisk firing, I was able to feel the texture and they have a very high grip as well as retaining the lines. I also really like the white porcelain interior with the black exterior. I think I will explore this further.
I am going to fire these in a test kiln to 1260, testing the colour and how the texture may change with vitrification.