Masterwork items are items with their name written in green text. My main is a scholar, so I can't tell you how to do anything with leather or armor, but typically masterwork jewels are crafted using special jewels made with Filigrees, starting with copper filigrees made from copper ingots.
Jewels able to be made into rings/earrings/amulets with copper tier bands/hooks/chains and settings can be fused in their raw form with filigrees via the discovery panel on the top. You'll discover an adorned jewel, which can then be fused with a crafting component and a setting to make a masterwork quality accessory.
Take note that your jeweling must be at level 50 to allow this, and you can craft higher quality jewels using silver, gold, platinum, mithril, and orichalum filigrees instead, all of which make special jewels capable of masterwork accessories. Take note as well that the special jewel itself is considered masterwork.
Make two "parts" of a weapon (staff head, staff shaft, for example), then make an Insignia. Enter Discovery Mode, and combine the three parts. You make something, getting double Craft XP for it and putting it on your recipe list.
BUT! They want Masterwork (green) or better. So: Do the above, with different combinations, until they unlock "Master" insignias. These use a bit more materials, but they give green items as their results.
(To make green items after you've Discovered them, just make them from the recipe list.)
Now, for Jeweler, it's similar, but different.
Normal: (Gem) + Setting + (Hook/Chain/Band)
Once you get far enough: (Gem) + Filigree = (Jewel) - an advanced form of the gem, basically.
Then just replace "Gem" with "Jewel" in the "Normal" pattern to make green items. --- "As the good archmage often admonishes me, I ought not to let my mind wander, as it's too small to go off by itself." -Danilo Thann
what level are your WS? just craft the things that require mythril ingot x 3 and wood log x 2 or is it the other way around. the thing you need to put with the blood or bones or whatever. those are all masterworks and they will still be used later on in my opinion, so just craft those. or if you WS is not that high level, there are also lower levels starting at 25 that use how many coppers and aspen wood to craft. in other words just craft 40 of this http://wiki.guildwars2.com/wiki/Bronze_Plated_Dowel or this http://wiki.guildwars2.com/wiki/Mithril_Plated_Dowel. all very cheap and can be sold to pretty much the same money back. i prefer crafting mythril ones if you decide to craft rares later on. --- There is only one word for noobs when playing DOTA 2........UNINSTALL
Dang! So that's what it was. I didn't realize the Plated Dowels were, themselves, masterwork. I just knew I had 3/40 from making only one thing, earlier in the month. (Something for someone, which is why it was an isolated incident. I've been hoarding materials for the real work of the monthly. But now I don't have to.) --- "As the good archmage often admonishes me, I ought not to let my mind wander, as it's too small to go off by itself." -Danilo Thann
I just transmogrified up the chain to Orbs and got my 40 just from drops... Pebble -> Nugget -> Lump -> Shard -> Crystal -> Orb
NOTE: Crystals and Orbs are the Masterwork & Rare ranks, so you need to fairly into Jewelry to do this... --- Skyrim is the girl who keeps breaking my heart, yet is so hot I still keep coming back on the chance I may get to sleep with her again. - Spurner