Boiled juice is ready for gelling if its drop does not spread on a cold plate. Store marmalade in cardboard boxes at room temperature.
Sort raspberries and currants, rinse, put in a saucepan and pour water so that it only covers the berries. Put on fire and cook until softened.
Throw on a fine sieve and wipe. Put the resulting thick juice on a slow fire and reduce by half.
Add sugar, citric acid and cook, skimming continuously, for 35–40 minutes.
Pour into flat molds in a layer 2.5-3 cm thick and leave overnight at room temperature. Cut into equal cubes, each roll in sugar.