Slice carambola crossways into 5mm slices.

Drizzle half the lemon juice over the carambola slices.

Cover the carambola slices with cold water.

Place in the freezer for 6 hours or until frozen.

Combine tea leaves, mint, and sugar in a large heatproof bowl.

Pour boiling water over the tea mixture.

Set aside for 15 minutes to brew.

Strain tea through a fine sieve into a large jug.

Add remaining lemon juice to the tea.

Set aside for 30 minutes to cool.

Pour tea into tall glasses.

Remove carambola ice from the freezer.

Break the carambola ice into pieces, with one slice in each piece.

Place a few carambola ice pieces in each glass.

Serve immediately.