Gems System

Sockets or slotkets?

Borrowing a page out of SquareSoft's playbook, Blizzard has included socketed weapons and armor in Diablo 2. As you play, you'll come across various gems like diamonds, emeralds, topazes, rubies, etc. Monsters might drop these, or sometimes you'll find gem shrines that yield a nice little rock. Each of these gems has specific properties, depending on what kind of gem it is and what type of armor or weapon you place it into. For example the ruby will enhance weapons with fire damage, impart fire resistance if placed in a shield, or add to your life if placed in a helmet. See the screenshots for more examples of what different types of gems will do. Keep in mind that different weapons and armor will have different numbers of sockets to place gems. If you have a sword for example, with 3 (the most we've seen so far) sockets, you can place 3 different gems in it to give you a customized weapon with lots of magical properties!

Rubies give you...

Emeralds

While Final Fantasy 7 allowed you to place and replace magical "materia" in your weapons sockets, the gems you put into sockets in Diablo 2 are not removable. You'll have to think carefully about what gems you're placing into which weapons because the process doesn't appear to be reversible.

How do you know?

As James mentioned, earlier, mousing over weapons that are on the ground will give you a clue as to whether or not they're worth picking up. A weapon name written in white tells you the item is common. Blue titles mean a magical weapon. Yellow signifies a rare "named" item. Green indicates part of a full set of special weapons. The socketed weapons and armors are designated with gray titles.

Diamond

Topaz

Magical item or socketed item?

Are gems and gemmed items worth picking up? Considering that weapon sockets give your weapon enhanced damage depending on the gem (rubies for fire, emeralds for poison, etc.), we'd have to say definitely. At least, it's worth it if you don't have a good magic or rare item already. Sockets and gems can give plain old items some real value! Imagine tacking on 2-5 fire damage to an enemy with every hit? Or 4 poison damage after a hit, per turn? It really adds up! Using socketed armor can be just as fun. Depending on if you put a gem into your shield or your helm, you can get bonuses for resistance to certain properties (fire, cold, poison, etc) or bonuses for your life, mana, and other characteristics. Maybe it's a bit useless to get a socketed shield and gem it (I've never been a big believer in resistances), but the helm bonuses are certainly worthwhile.

A regular dagger...with a socket!

Stick an emerald in and voila - poison dagger