Place three sheets of gelatine into a bowl of cold water to soften.
Pour the apple juice into a pan and add in a tablespoon of sugar. Stir and heat over a medium heat until the sugar has dissolved and the juice is hot but not boiling. Remove from the heat. Squeeze the excess water from the gelatine sheets then add them into the apple juice and stir until fully dissolved. Pour the apple juice into four glasses then place in the fridge to set for a few hours. Once set, place the remaining three sheets of gelatine into a bowl of cold water to soften and place the cranberry juice and remaining tablespoon into a pan and heat over a medium heat.
Once the sugar has dissolved and the juice is hot, remove from the heat, Squeeze the excess water from the gelatine and add into the cranberry juice. Stir until dissolved then leave to cool.
Once luck warm, remove the chilled glasses with the apple juice from the fridge and lay a layer of mandarins (no juice) on top of the apple juice.
Pour the cooled cranberry juice into each glass then place back in the fridge to set.
Once set, top each jelly with a mandarin and serve.