Prepare the Fruit Mixture: In a large mixing bowl, combine the chopped pineapple, glace cherries, maraschino cherries, dried apricots, raisins, sultanas, prunes, and crystallized ginger. Pour the dark rum over the fruit, stir to coat, and let sit for at least 1 hour to absorb the flavors.

Preheat the Oven: Preheat your oven to 325°F (160°C) and line a round cake tin (about 8 inches) with parchment paper.

Prepare the Batter: In a separate large bowl, cream together the softened butter and golden caster sugar until light and fluffy. Incorporate the eggs individually, mixing thoroughly after each addition.

Combine the Dry Ingredients: In another bowl, sift together the flour, baking powder, mixed spice, and ground nutmeg. Slowly incorporate the dry ingredients into the creamed mixture by folding them together.

Add Zests and Marzipan: Stir in the lemon and orange zest, then gently fold in the soaked fruit mixture and marzipan pieces until evenly distributed.

Bake the Cake: Spoon the batter into the prepared cake tin, smoothing the top with a spatula. Arrange the blanched almonds and maraschino cherries on top as a decorative garnish. Bake for 1.5 hours, or until a skewer inserted into the center emerges clean. If the top begins to brown too rapidly, lightly cover it with foil.

Cool and Serve: Allow the cake to cool completely in the tin before removing. Serve it as is, or wrap in parchment and foil to store for up to a week. This cake is delicious on its own or served with a dollop of whipped cream.