I use the fruit from the flowering quince. Wash and chop in quarters and cover with water. Simmer until they have the consistency of boiled potatoes. Pour into a strainer, I use the feet and legs of clean hose, and let drip. Measure your juice and add 3/4 cups sugar for each cup of juice. Bring to a boil and cook until it sheets all a spoon. There is a recipe on this site, that may give better directions than mine.