In a small pan, bring pomegranate juice to a boil over medium heat. Continue to boil until liquid is reduced by half. Set aside to cool.
If desired, rub the rims of 2 serving glasses with lime juice and dip in salt.
Divide pomegranate syrup between the two glasses, then add crushed ice on top.
Add ice, tequila, triple sec, orange juice, and lime juice to a shaker. Shake for 5-10 seconds until the shaker is frosted.
To achieve the "ombre" effect, gently pour mixture over a spoon on top of the ice in the serving glasses. Garnish with lime and pomegranate arils before serving, if desired.