Eternal Fire

Eternal Fire is a material used in crafting recipes.

Source
It is not acquired directly, it is created by combining 10 Crystallized Fire.

It can also be obtained from Transmute: Eternal Life to Fire and Transmute: Eternal Water to Fire.

Alchemy

 * Transmute: Cardinal Ruby
 * Earthsiege Diamond
 * Transmute: Eternal Fire to Life
 * Transmute: Eternal Fire to Water
 * Transmute: Eternal Might

Blacksmithing

 * Helm of Command
 * Hellfrozen Bonegrinders
 * Icebane Chestguard
 * Icebane Girdle
 * Icebane Treads
 * Ornate Saronite Gauntlets
 * Plate Girdle of Righteousness
 * Savage Saronite Gauntlets
 * Spiked Deathdealers
 * Vengeance Bindings

Enchanting

 * Enchant Cloak - Superior Frost Resistance
 * Enchant Weapon - Icebreaker

Engineering

 * Charged Titanium Specs
 * Nesingwary 4000

Jewelcrafting

 * Savage Titanium Band
 * Savage Titanium Ring
 * Titanium Frostguard Ring
 * Titanium Impact Band
 * Titanium Impact Choker
 * Windfire Band

Leatherworking

 * Ice Striker's Cloak
 * Icy Scale Belt
 * Icy Scale Boots
 * Icy Scale Chestguard
 * Polar Boots
 * Polar Cord
 * Polar Vest
 * Trollwoven Girdle
 * Trollwoven Spaulders
 * Virulent Spaulders

Mining

 * Titansteel Bar

Tailoring

 * Deathchill Cloak
 * Glacial Robe
 * Glacial Slippers
 * Glacial Waistband
 * Sapphire Spellthread
 * Spellweave