In a small saucepan, add sugar, water, and ginger. Bring to a boil, stirring until sugar has dissolved. Let simmer for 10 minutes. Turn heat off and let steep until completely cooled.
In a blender add water and Sodium alginate. Blend for 1 minute until there are no lumps and mixture is cloudy. Pour into a glass bowl and let sit for 1 to 2 hours, until mixture is not cloudy and any bubbles are gone.
In a bowl add ginger simple syrup, vodka and mint. Muddle to release oils. Strain. To mixture add lime zest, juice, and calcium lactate, whisk well until all calcium lactate has dissolved. Let sit for a few minutes.
Using a rounded tablespoon measuring spoon, scoop full with cocktail mixture. Submerge into bath, when spoon is fully submerge flip over and gently shake mixture out. Ball should release and drop to the bottom of bowl. Leave for 1 minute. Remove from bath with slotted spoon. Place in clean water bath to rinse. Remove to spoon. Garnish with flaky sea salt and lime rind. Serve.
Can be made only 20 minutes before, center will solidify the longer it sits.