Chop the chocolate finely and melt over a hot water bath. Separate the eggs and beat the yolks with the sugar until foamy over a hot water bath. Beat the egg whites with a pinch of salt until stiff. Stir the rum and melted chocolate into the egg yolk mixture until frothy. Whip the cream. Fold the egg whites and whipped cream gently into the egg yolk mixture.
Line a loaf tin (1 liter capacity) (approximately 4 cups) with plastic wrap, pour the chocolate mixture into the tin and place in the freezer for at least 6 hours. Thaw before serving for half an hour, turn out from the tin and remove the plastic wrap. Cut with a knife dipped in hot water into slices and serve garnished with raspberries.