Soak the carrageen in hot water to cover for about 15 minutes (or reconstitute according to package instructions), then drain discarding the soaking liquid. Put into 600 ml fresh water with the honey, lemon juice and rind. Bring to a boil and simmer for 25-30 minutes. Strain and discard the carrageen, and let the liquid cool slightly. Meanwhile, combine the beaten egg white and the whipped cream, then gently fold the mixture into the carrageen liquid. Pour into a greased mold and chill. . (Carrageen [or "carrageenan"] can usually be found in health food stores.)