Ri'Dariit can take them from you. But if you are the crafting type, you might hold on to them. Once researched certain traits, this one will require them to add traits such as "Enduring". Many crafting guides have information out there. If Batranu doesn't make weapons or armor, it can sell them for coin around crafting stations by using /say. Or better, give a friend or guild member.
Fusozay Var VarJaji kor nirni. Ri'Dariit ahnurr shir Gouranga an vasa rid-t'har.
I get they can add traits, but how? I haven't seen an option in the crafting interface to add a gem, and when I right click the gems, I don't get an option to enhance an armor piece.
At the bottom of the crafting interface is an option to select a Trait; if you don't KNOW any Traits for the item you're crafting, it'll just be an "X" I think... but if you know the Trait for an item, that Trait's requisite gem will be listed at the bottom in the Traits section. If you know MULTIPLE Traits for the item you're crafting, each of the Traits' gemstones will be listed and you have to select (presumably only one Trait per item).
Since I don't want to burn the gems on items in the early levels when I'm swapping gear two or three times PER level, I've been storing them on an alt (because there is no room in the bank *cough cough*).... so that I can use them on the "good" gear I will EVENTUALLY craft.
Personally, if you're not going to craft traits into your items while you level, I'd save the gems on an alt or in the bank. Those gems you're finding at level 5 are the same ones people will be using to add traits to level 50 veteran gear. It's my suspicion that the price of gems will rise once a lot of people are hitting endgame.
I get they can add traits, but how? I haven't seen an option in the crafting interface to add a gem, and when I right click the gems, I don't get an option to enhance an armor piece.
You incorporate them while crafting the item, and you have to research the trait first. To research a trait for an item, you need to have an item OF THE SAME TYPE that has that trait, and then use the research tab at a crafting station to destroy the item and start researching the trait. Research takes a certain amount of real time, starting at 6 hours for each item type but increasing as you learn more traits for that item.
After you've learned the trait, if you have the right trait gem, you'll have the option to add the trait to the item in the item creation screen.
Traits are useful not just because they improve your gear; you also need to have learned a certain number of traits for an item before you can craft that item type at the special world crafting benches, which allow you to make item sets with unique properties.