Raw Green Steel ingredients

Altar of Fecundity Raw Ingredients
Available as chest loot in The Vale of Twilight adventure area and quests within the area. Components listed by Quest:


 * Eberron Energy Cell - vendor next to the altar
 * Medium Splintered Horn - The Shroud phase 2 and 3
 * Large Splintered Horn - The Shroud phase 4 and 5

Altar of Invasion Raw Ingredients
Available as chest loot in The Shroud phase 1 and 2
 * Small Glowing Arrowhead
 * Small Gnawed Bone
 * Small Length of Infernal Chain
 * Small Devil Scales
 * Small Twisted Shrapnel
 * Small Sulfurous Stone
 * Shavarath Low Energy Cell - also phase 3 vendor next to altar
 * Shard of Power

Altar of Subjugation Raw Ingredients
Available as chest loot in The Shroud phase 3 (optional and end chests)
 * Medium Glowing Arrowhead
 * Medium Gnawed Bone
 * Medium Length of Infernal Chain
 * Medium Devil Scales
 * Medium Twisted Shrapnel
 * Medium Sulfurous Stone
 * Depleted Shavarath Medium Energy Cell - also phase 3 vendor next to altar
 * Shavarath Medium Energy Cell
 * Shard of Great Power

Altar of Devastation Raw Ingredients
Available as chest loot in The Shroud phase 4 and 5
 * Large Glowing Arrowhead
 * Large Gnawed Bone
 * Large Length of Infernal Chain
 * Large Devil Scales
 * Large Twisted Shrapnel
 * Large Sulfurous Stone
 * Depleted Shavarath High Energy Cell - also phase 3 vendor next to altar
 * Shavarath High Energy Cell
 * Shard of Supreme Power

Note :
 * All Altar of Invasion, Subjugation, and Devastation Raw Ingredients can also be acquired from Devil Assault on Elite or Epic Difficulty. This includes Shards.
 * The chest at the end of Part 2 of Tower of Despair has a chance for Altar of Subjugation Raw Ingredients. This includes Great Shards.
 * Various chests within the Tower of Despair flagging quests also have a chance for ingredients from the three Altars. This may or may not include Shards.

Raw Ingredient supply and demand
In general:
 * (Most demanding) Scales > Stone > Arrow = Chain > Shrapnel > Bone (Least demanding)

However, this isn't necessarily true, since some combinations are more worthwhile than others. For a better estimate of ingredients' relative worth, simply check the auction hall prices.