Lladro lithophanes include a LED with battery to emit light. However, appropriately sized candles may also be used. When lighting the LED or the candle, the transparency of the porcelain allows the light to bring out the patterns etched on the surface.
Lithophane means "transparent stone", and refers to those designs engraved on porcelain or stone (alabaster or transparent marmor) that appear with three-dimension effect when light is applied from inside or from its back. Best known are Bernardaud Lithophanes or candle votives, although there have been many makers and carvers in 19th century applied arts.
From our blog: Lladro Lithophanes - "Light in Stone".