Bring a large nonstick saucepot of water to a boil and generously salt. Transfer ½ cup boiling water to a bowl and stir in the saffron; reserve. Add the rice to a boiling water and cook, stirring occasionally, for 5 minutes. Drain well. Melt the butter in the same pot over medium-low heat and stir in the coriander and cumin. Reduce the heat to low and spread one-third of the rice evenly across the bottom. Sprinkle with one-third of the saffron mixture and half of the cranberries and currants. Spoon half of the remaining rice over the dried fruit and sprinkle with half of the remaining saffron mixture and the remaining dried fruit. Top with the remaining rice and saffron mixture. Poke 5 holes in the rice with the handle of a wooden spoon. Wrap a clean kitchen towel around the pot lid, cover the rice, and steam for 35 minutes. Remove from the heat and let stand for 10 minutes. Spoon the rice, including its crunchy golden bottom layer, onto a serving platter and top with the almonds and pistachios.