what herbs and spices are in angostura bitters?
['For the Bitters.', '1/2 cup whole cloves.', '1/4 cup whole black cardamom.', '3/4 cup blades of mace.', '2 tablespoons whole allspice berries.', '1/4 cup cinchona bark (available at Kalustyans and Herbs of Mexico.)', '1 heaping teaspoon gentian root (available as chips and twigs from Mountain Rose Herbs)']