This simple jelly recipe sets up from the magic of lemon juice and the natural pectin in the raspberries. You can process your jars to can for shelf-life, or keep them in the refrigerator to extend their life. Honestly, in the refrigerator with no processing, I've opened jars many months after summer and they are still perfect. With this jelly though, I fear there won't be any left to enjoy at a later time.... I use a varied array of jar sizes and shapes, faceted ones especially show off the jelly's color. Sort the raspberries well, but I don't wash mine, to preserve the glorious raspberry essence. Raspberry jelly is perfection on a piece of good toast slathered with labneh. My sister likes hers in cocktails.
In a large, heavy pot, combine the raspberries and water. Stir constantly and bring to a boil. Reduce the heat and simmer for 5 minutes.
Line a fine mesh sieve with a few layers of dampened cheesecloth, set over a large bowl in the sink, and pour the raspberry mixture through, catching the juice in a large bowl. The juice should measure about 4 cups.
Clean the large pot of any residual raspberry pulp and seeds. Filter the juice back into the pot, again through the sieve lined with a fresh round of dampened cheesecloth layers. Add the sugar, lemon juice, and rose water. Bring to a boil and cook for 10 minutes, then skim off the foam. Return to a boil and cook until the jelly reaches 220 degrees on an instant-read thermometer.
Ladle into clean jars, and close the lids tightly. Store in the refrigerator.