Wash tangerines thoroughly and zest 3 tangerines using a fine grater, being careful to avoid the bitter white pith. Set zest aside.

Juice all 6 tangerines to obtain approximately 2 cups of fresh juice. Strain through a fine-mesh sieve to remove pulp and seeds.

In a medium saucepan, combine tangerine juice, 1/4 cup honey, and tangerine zest. Heat over medium heat until mixture is warm but not boiling.

In a separate bowl, sprinkle agar-agar powder over 1/2 cup of cold water and let bloom for 2 minutes.

Add the bloomed agar mixture to the warm tangerine juice, stirring constantly. Bring to a gentle boil over medium heat, then reduce to low and simmer for 3-4 minutes, stirring frequently until agar is completely dissolved.

Remove from heat and strain the mixture through a fine-mesh sieve into a clean 8x8 inch square dish to remove zest pieces.

Allow to cool at room temperature for 15 minutes, then transfer to refrigerator and chill for 3 hours until completely set and firm.

While jelly sets, prepare honey syrup by combining 1/2 cup honey with 2 cups water in a small saucepan. Heat gently until honey dissolves completely. Add a pinch of salt. Cool completely and refrigerate.

Once jelly is fully set, use a sharp knife to cut into 1-inch cubes. Dip knife in cold water between cuts for clean edges.

Arrange jelly cubes in individual serving bowls or a large serving dish. Pour chilled honey syrup over the cubes just before serving. Garnish with fresh mint leaves or pomegranate seeds if desired.