Beat the butter together with the sugar, blood orange and lemon zest and juice.
In a separate bowl, sift together the flour, salt, rosemary, ginger, and cardamom until blended.
Add the flour until only just combined with the butter mixture. The dough should be thick and crumbly.
Cut the dough into about two halves, and roll each into a cylinder on a floured surface.
If the dough is sticky at this point, wrap it in wax paper and refrigerate it for an hour or two until it firms up.
Preheat the oven to 350 F when you are ready to bake.
Slice the cookie dough cylinders into rounds about 1/2-inch thick.
Place them on a baking sheet about 1-inch apart, and bake in the oven for about 15 minutes, until just beginning to brown at the edges.