There are some general rules to follow when gemming an item:
- Guild progression.
- How many sockets are on the item?
- What color is the socket?
- Is your meta active?
- What are you using the item for - EH, avoidance, or threat?
- What is the bonus?
Rule 1: Guild Progression
Guild progression is first for a single reason, Effective health (or EH). Short version, EH is the total amount of damage you can take without a heal before you die through a combination of stam, armor, and things like the mother bear talent and defensive stance. Avoidance has no effect on EH. The best way to help your guild progress as a tank in new content is by gearing for EH.
What does this mean? When gemming for guild progression you will have 24 stam gems in every slot and (unless there are 12 stam socket bonuses) you will never match a socket that is not blue. (On a personal note Xav and I were discussing how we both felt that avoidance has never been weaker than it will be in 3.1, based on the Ulduar encounters that we have tested on PTR so far.)
Rules 2 and 3: Number and Color
The next two rules are almost interchangeable, except when you consider that the bonus for matching a single socket will be something like 4 agi 8 ap or 6 stam, while the socket bonuses for matching 2 sockets are 1.5x more, 6 agi 12 ap or 9 stam.
My thought process on these two looks something like this:
It is that simple sometimes. Even if the bonus is bad, through a combination of 16 agi gems, 8 agi 12 stam gems, and 24 stam gems, you will almost never lose out by matching any socket that does not require a yellow gem (more on this in the summary).
This leaves 4 possible items, as only one item in LK has 3 sockets. Those 4 items are items which contain:
- 1 yellow socket
- 2 yellow sockets
- 1 red socket 1 yellow socket
- 1 blue socket 1 yellow socket
Rule 4: Meta
The next rule is one that does not come up very often but is something that must be addressed immeditaly: Is your meta active?
- The only meta that one might possibly use as a tank that has a yellow as a requirement is the RED. While I would strongly recommend against using it, if you are and you only have one yellow socket in all your gear, it is a given you will match the bonus no matter what it is.
- If you need either a red or blue gem to activate your meta and your gear only has enough sockets to just meet the meta requirements regardless of socket color, chances are your gear is at the point you still need to stack 24 stam gems and this is a null argument.
- If you do not have enough blue or red slots to met the meta and you wish to match the bonus that leaves you with an 8 hit/12 stam if you need a blue for your meta, and either an 8 agi/8 hit or an 8 hit/8 expertise if you need a red for your meta.
Rules 5 and 6: Item Purpose and Bonus
Finally, you need to look at what set you are going to put that item into. This is also the first place the socket bonus will actually matter.
- 1 yellow socket: As we already mentioned, items with only a single socket generally have weaker bonuses. As such, when using the item for pure EH, you will never match this bonus. For threat, you will always match this using either a 16 hit or an 8 hit/8 expertise. Now for avoidance, finally the bonus maters. If the bonus is an agi bonus then match it with an 8 agi/8 hit. Otherwise, use a straight 16 agi gem.
- 2 yellow sockets: Only one item in the game so far has two yellow sockets, but there will almost definitely be more. Again, no bonus can make up for the amount of EH lost by using 2 yellows gems. For threat, this is an amazing combination and you will match any bonus with any 2 16 hit or 8 hit/8 expertise gems. For avoidance, while a single slot trades 4 agi for 8 hit, here you trade 10 agi for 16 hit. Especially if you have already matched a lot of single yellow slots, it is probably best to avoid this bonus even if it is 6 agi in your avoidance set (and that was definatly not on purpose).
- 1 yellow 1 red: 3/3, yellow gems for EH just do not work. For threat this is another dream combo, and will match the bonus no matter what it is, only now you can also use a 16 expertise gem. For avoidance, you are trading 2 agi for 8 hit, so an agi bonus would absolutly be worth it.
- 1 yellow 1 blue: Finally, a yellow socket you will want to match for EH, using an 8 hit/12 stam along with a 24 stam to match a stam bonus, but avoid other bonuses. This is a decent combo for threat if the bonus is hit or expertise, using an 8 (insert more needed stat)/12 stam gem and a 16 hit (or 8 hit/8 expertise if the last insert was expertise). Avoid this for avoidance (/sigh I know I know) even if it is an agi bonus.
As you can see, only in 4 possible configurations of sockets did the bonus even matter, and in even more cases you will pick up extremely sub-par bonuses simply because the color was good. Take the free bonus and move on. Lets be real you would never gem a yellow in a 6 stam blue socket or a 4 agi red would you? So why gem a yellow for an 8 ap blue or 4 crit red socket? Even though I have personally already stated my disgust at that bonus on our t8 shoulders, I am still going to get it simply because it is there, it is red, and it is free. Also, activating your meta is not something that comes up very much, but having a dead meta happens more than you would think (last time I did it I did not notice for 3 weeks because it was my DPS meta) and you do not want to be that guy who gets called out on vent "hey dark, where is your second blue gem for your RED?" And yes for those who may be new to the game, the BC version of the RED took 2 of every color to activate.
Sorry, this is actually a lot longer than I thought it would be so for Jewelcrafters, consider yourself lucky. You not only never have to worry about your meta, but you have extreme versatility. You can pick up those 9 stam and 6 agi yellow bonuses. Number 6 holds much much more importance to you than it does non JCers, but you cannot ignore the others. A double yellow is not the place to put 2 prismatics to pick up a bonus, and if you can avoid it never put 2 prismatics in the same item. You still want to gem 41 stams for progression, and you can use 27 hits or expertise gems in blue slots for your threat pieces.
Like I said this is getting way to long so again I apologize for there being nothing in 2 weeks as I will be without internet till the 6th and I simply did not have enough time to finish my next topic (since I wanted to get the threat write-up done before PTR closed). I may put it up later in the week after I get back we will have to see.