In a cocktail shaker, pour in the orange juice, lemon juice, elderberry syrup, and ground turmeric. Fill the shaker about three-quarters full with ice. Secure the lid and shake vigorously until the mixture is thoroughly chilled.
Strain the blend into a rocks glass filled with fresh ice for a smooth presentation. Alternatively, if you prefer a layered effect, shake only the citrus juices and turmeric first, then strain over a glass filled with crushed ice. Gently pour the elderberry syrup over the top to create a vivid gradient.
Finish with a splash of sparkling water and, if you like, an orange slice on the rim for a bright and festive touch.