Slice one orange wheel and cut into small triangles
Add one piece of orange to each segment of an ice cube tray
Add a few rosemary leaves to each ice cube
Top with cold water and freeze for 6 hours or overnight
Peel the remaining orange and run peel around the rim of the glass
Fill glass with orange and rosemary ice cubes
Top with one measure of Sibling Negroni gin
Top up with tonic water
Add a sprig of rosemary and stir
Serve immediately