Grind black and white mustard seeds, add the water and stir thoroughly. Leave to stand at least 30 minutes. Grind the dry spices and add to mixture. Add salt, turmeric and sugar. Add vinegars and cider. Stir well. Don't worry if it appears sloppy at this stage. It will thicken as the liquids are absorbed. Cover and leave for 24 hours then bottle and seal.