OK this is Unholy[S]haman and you are reading my “[Guide] Gems and how to work 'em”.
This is a mixture between my guide and the guide on the official world of warcraft forums, i added in alot of information from there because it explains it best.
I have noticed over the past few months that there are still many players that are still not too clued up about how sockets, socket bonuses and just gems in general work. So I thought I would write this guide to make your life so much simpler.
Lets start with gems:
Gems were introduced along with the Jewelcrafting Profession in the World of Warcraft Expansion: The Burning Crusade.
The new profession Jewelcrafting allows jewelers to prospect ore into amazing gems, these gems also have a chance to drop of normal NPC's and can sometimes be mined out of outland veins.
Another thing that Jewelers can do is cut these gems into more useful gems (Think of it like a miner finding a piece of carbon, then a jeweler cutting it into a diamond – this is in real life btw lol).
There more useful gems can now be “socketed” into equipment that allows it.
Sockets:
A socketed item is like any other item in World of Warcraft, except that it can be upgraded by attaching magical gemstones into the item itself. This imbues the item with additional powers similar to an enchantment. You will also notice that the items that allow for these enhancing gems to be socketed, also are color coded. Meaning it gives you a guide line on what gems to put into this item.
Here is something that still a lot of experienced players do not know: Just because an item has a red socket, blue socket and another red socket, means that you have to follow it, you could of course put any color gem into any of those sockets. However! You will not get the socket bonus, a socket bonus gets activated when the correct color gems are put into the correct color sockets, E.G. Red gem in a Red socket. The socket bonuses are normally something small and insignificant but if you trying to gear up, any bonus can be useful.
Socketing Gems:
If an item has sockets, shift-right-click on it to bring up the item's socketing window. Here, you can simply drag and drop gems from your inventory to the sockets. Once you are satisfied with your selections, click the "Socket Gems" button at the bottom of the window. Be aware that socketing is permanent - the gems are permanently affixed to your socketed item and there is no way to undo your decision.
This item requires a red gem and two yellow gems to gain a socket bonus.
Placing a Red, Blue and Yellow gem into the socket will give the item the
inherent bonuses of those three gems, but not the socket bonus.
Placing a red and two yellow gems in the corresponding sockets will
grant the item the gems' inherent bonuses, as well as the socket bonus.
The sockets will sparkle if the matching gem color is put inside it.
Meta Gems:
Meta sockets and gems are rare and provide powerful bonuses. Meta sockets will only accept meta gems, and meta gems can only be used in meta sockets. Meta gems can have their own special requirements unique to each meta gem. If these particular requirements are not met, the gem will not work and remain greyed out.
Item socketing window of a socketed item with
a meta gem slot and a normal gem slot.
A meta gem's characteristics and requirements.