In a small saucepan, over medium heat, combine the water and sugar. I Bring to a boil and cook for 2 minutes. Remove from the heat and cool completely.
Using a sharp knife, remove the outer skin of the melon. With a spoon, scrape out the seeds and discard. Dice the melon into small pieces. In the cup of a blender, combine the melon and simple syrup to taste. Process until smooth. Add the vodka and process until smooth.
Pour the mixture into nonreactive cake pan and freeze until firm. Remove from the freezer and allow to sit for a couple of minutes. Using a knife, scrape the melon mixture back and forth, spoon the mixture into a plastic container with a lid. (**The consistency of the mixture should be slushy) An electric ice cream machine can also be used. Cover and freeze until ready to use.
Place the rock salt on the large oval platter. Lay the oysters on top of the salt. Place the flowers around the oysters. Spoon some of the Melon/Vodka Granita over each oyster.
Top the granita with some of the caviar. Garnish with parsley.
Yield: 4 to 6 servings