Fiery Ingots can be used to make a Fiery Sword, a Fiery Pickaxe, or the four armor pieces. To craft the sword and pick, use blaze rods where you would normally use sticks. Fiery items are stronger than diamond items, and just as durable.
The Fiery Sword is automatically enchanted with Fire Aspect II. The armor pieces are automatically enchanted with a unique enchantment called Fiery Aura II. The Fiery Pick is not automatically enchanted, but has the innate property of automatically smelting all the blocks it mines.