Porcelain is very strong and therefor can be made extremely thin. Even such that is becomes quite translucent. So, I had to experiment with this in combination with LEDs. Making a (actually many) mold in a funnel shape with a hole at the bottom allowed to experiment with different thicknesses and multiple layers. You simply fill the mold with castable porcelain and wait approximate 10 seconds and let the access porcelain pour out again.  The layer thickness that remains in the funnel is depending on the time you let the porcelain dry.