Core Leather

Core Leather is rare leather found only by skinning high-level beasts in the Molten Core. It is used in a variety of high-level recipes.

Source
This item can be found by skinning any of the core hounds and Magmadar in Molten Core, and Ancient Core Hounds in the Firelands.

As an ingredient
Core Leather is used in the following recipes:

Blacksmithing

 * Dark Iron Boots
 * Dark Iron Gauntlets

Leatherworking

 * Chromatic Gauntlets
 * Core Armor Kit
 * Corehound Belt
 * Corehound Boots
 * Lava Belt
 * Molten Belt
 * Molten Helm

Tailoring

 * Bottomless Bag
 * Core Felcloth Bag

As a quest objective

 * Favor Amongst the Brotherhood, Core Leather