In a pitcher, mix together pineapple juice, gin, and lemon juice. Divide between 2 tall (Collins) glasses. Pour 1 teaspoon creme de cassis in the center of each glass; do not stir. Carefully fill glasses with ice cubes, and garnish each with a pineapple wedge.
You can prepare these cocktails without the pineapple garnish, if desired.
This didn't work so well for me, The juices mix with the creme de cassis, even if you pour it slowly. But it tasted good.