A gnome hooked hammer is a double weapon—an ingenious tool with a hammer head at one end of its haft and a long, curved pick at the other.
The hammer’s blunt head is a bludgeoning weapon that deals 1d6 points of damage (crit ×3). Its hook is a piercing weapon that deals 1d4 points of damage (crit ×4). You can use either head as the primary weapon.
Gnomes treat hooked hammers as martial weapons.
Pathfinder RPG Core Rulebook. Copyright 2009, Paizo Publishing, LLC; Author: Jason Bulmahn, based on material by Jonathan Tweet, Monte Cook, and Skip Williams.
Pathfinder Roleplaying Game: Ultimate Equipment (OGL) © 2012, Paizo Publishing, LLC; Authors: Dennis Baker, Jesse Benner, Benjamin Bruck, Ross Byers, Brian J. Cortijo, Ryan Costello, Mike Ferguson, Matt Goetz, Jim Groves, Tracy Hurley, Matt James, Jonathan H. Keith, Michael Kenway, Hal MacLean, Jason Nelson, Tork Shaw, Owen KC Stephens, Russ Taylor, and numerous RPG Superstar contributors