The Queen's Emerald - The Iungetellus Chronicles, #1

In Axella's world, the pirates' existence is as old as the land and the sea. The attacks directed at trade ships or harbors are the only events that disturb the peaceful life on the continent of Iungetellus. Axella has had contact with pirates only through rumors or during their attempts to rob Portus Avorum, the city where she lives. Until the moment when, during such an attack, Axella's brother, Maximinus, manages what few ever could: to face the most famous pirate in history - the feared Calogerus - and force him to retreat.
Not long after this, Calogerus' people kidnap Maximinus and Axella's mother, asking for a ransom that's almost impossible to obtain - the Queen's Emerald, a treasure hidden in the heart of a realm in Bazanthos, the continent east of Iungetellus. Before their time runs out, Axella and Maximinus must venture from one continent to the other to steal one of the most precious possessions of the realm of Eratrix.
Faithful friends will support them, unexpected enemies will try to undermine them, and their mission will bring to light truths that will change their lives and the world they know forever.