Ethereal Sheet of Metal
This is one of the harder aspects of the PoP Armor Quests to complete. I highly recommend that you check The Bazaar on your server for any Ethereal Sheets of Metal before you attempt trying to complete this arduous task. Alternatively you could buy Celestial Essence if any are available which will cut the time it takes you to complete this task in half.
Those of you out there who don't mind a little Tradeskilling and farming some lower level enemies... Well maybe you'll enjoy this part of the armor quest! Now as aforementioned the very first difficult thing we need is Celestial Essence. This is obtained quite a few different ways, let's first start off with the vendor purchased aspect of it. Head on over to Darius Gandril (on Find) in the Plane of Knowledge.
From him I recommend you purchase both Celestial Solvent as well as Concentrated Celestial Solvent. The regular Solvent allows you to do single combines and the Concentrated stuff allows you to combine 3 items at a time. The items that you'll be combining to make the Celestial Solvent are the random Runes, Pages and other assortment of crap that drops off enemies level 60 and below.
If you have no idea what I am talking about, I have compiled a list of materials that are used in crafting the Celestial Essence. Follow the link provided to head on over to that page and see exactly what it is we're looking for. Once you've done all the farming you need to do it's time to craft the item!
Celestial Solvent - Combine with 1 item to make 1 Celestial Essence
Concentrated Celestial Solvent - Combine with 3 of the same item to make 3 Celestial Essence
You will want to do all of these combines in a Mixing Bowl. Any Mixing Bowl works and the combine is no fail so you don't have to worry about blowing all your mats on nothing! Once you get the Celestial Essence(s) that you need the next part will be to make the Ethereal Temper.
Ethereal Temper
In order to make the Ethereal Temper you'll need 2 Celestial Essence (talked about above) as well as 1 Emerald Tea Leaf which you can purchase from Sirekoth Eshe (Eastern Trader Building in PoK). Additionally you'll need Soda which can be purchased from Chef Denrun or Caden Zharik in PoK.
Ethereal Temper has a 212 Brewing Trivial. The combine also must be done in a Tanaan Brew Barrel (found in PoK).
2 Celestial Essence
1 Emerald Tea Leaf (EQ Traders Link)
1 Soda (EQ Traders Link)
Once you've made the Ethereal Temper there'll only be a single combine left for you to do which is the Ethereal Sheet of Metal that we're after. All the materials you need for the Ethereal Sheet of Metal are found below. Additionally anyone confused about the location of either the Tanaan Brewing Barrel or Tanaan Forge - just reference the screenshot below.
Ethereal Sheet of Metal
This is the final combine for Ethereal Sheet of Metal. The only item(s) we haven't talked about yet are the Brick of Ethereal Energy which drop almost any PoP mob as well as the Tanaan Smithing Hammer which is vendor purchased in PoK. Once you have all of the items together you'll need to do the combine in a Tanaan Forge.
Ethereal Sheet of Metal 212 Smithing Trivial - Tanaan Forge is found in Plane of Knowledge.
2 Brick of Ethereal Energy
1 Ethereal Temper
1 Tanaan Smithing Hammer