The Republic of Salt by Ariel Kaplan
Peace in one world always comes at a cost to the other.
Toba and Naftalys lives changed forever when Toba discovered the mirrored world of the Maziks beyond the Pomegranate Gate. In their search for answers, they must find their own ways to the wonderous and powerful neighbouring republic of Zayit. A magnificent city overflowing with olives, spices and saltbut not the safe haven they need. The republic has turned its back on fleeing Jewish and Mazik refugees, and is closing its ears to warnings of war.
Meanwhile, the tyrannical Mazik King Tarses is building his army to cross the sea to Zayit. With time running out, and his visions growing worse, Naftaly must convince his beloved Barsilay to rally the armies of the world and accept his role as the true heir to the throne. But Barsilay resents the fate thats been thrust upon him.
Toba knows that Zayit's fate is only the beginning: she must discover her own destiny to defeat Tarses by restoring the balance between worlds.
Unlikely alliances must be forged, impossible myths must be made real, and the city of Luz must be brought back from the depths of the sea.