Ooooooo blackberries! LOTS of blackberries! They make up wonderfully into jam (I don't mind the seeds which is just as well as they are a royal pain to remove). Now as to adding spice - here great care must be taken to insure flavor compatability. My suggestions would be a chile that does not have ANY "bell pepper" underflavors such as cayennes or yes perfectly ripe habs. The thought of such a concotion glazing a roasted duck is a pleasant one indeed. Just follow the recepie for jam inside the Sure-Jell or Certo or whatever pectin you use and add the chiles for the last boilup. I have no recommendation as to quantity but I would start low and then build. If there are as many berries as you indicated (my breath is coming in short pants!) maybe you could divide your batches and add different quantities (manybe different types of peppers?) to each. Keep careful notes and report back to us on your results! Peace, love and peppers Lorraine