Trader's Token

The Trader's Token is a rare currency in Salt. It can be turned in to a  Village Trader located in Trader Villages. For every five tokens you turn in, the village trader will give you a Village Key used to open one of the chest in the village.

Source
This item can be obtained by looting pirate chests or killing uncommon pirates, including:
 * Pirate Captain
 * Pirate Commander
 * Pirate Elite Captain
 * Pirate Shipwright
 * Pirate Scavenger
 * Pirate Elite Bounty Hunter
 * Silver Pirate Chest
 * Gold Pirate Chest

Bug

 * This item's description is actually mislabeled, saying "Turn seven of these". In truth, you only need five tokens to receive a village key.