Diablo II/Items

Gems
Gems are equipment enhancing items that only take up one slot of inventory space. You place them within socketed equipment and once placed, they can never be removed.

Each gem type (i.e. Diamond, Emerald, etc.) can appear with one of the following quality types:
 * Chipped
 * Flawed
 * Normal (note that these gems are labeled with only their type - it does not say "normal").
 * Flawless
 * Perfect

You might think that these would give players the upper hand, especially lower level players if they could get their hands on them, however the game limits this by giving each quality a level. This level, ranging from 1 (chipped) up to 18 (perfect) requires that the player socketing the item (or using it after socketing) be at least that level. So, a level 16 Paladin cannot socket a level 1 sword with a Perfect Skull, since the gem has a higher level than the player's character.

The following lists contain the various types of gems and qualities that can be found, along with their associated stats:

Emeralds
In Act 1, 3 emeralds of the poorest quality can give you a very good Bow or Crossbow. - Even possible to use in Act 5!

Potions
Potions are split into two main categories, recovery and ailment curing.

Recovery
Recovery potions help refill your health or mana, or both!

Rejuvination
Rejuvenation potions heal both health and mana instantly rather than over time. Powerful, but often misused.

Stamina
Not so much of a remedy for an ailment, but it does cure "fatigue" by maxing out your Stamina for thirty seconds or so before it begins to drop like normal.

Antidote
Used to remove the poison status, antidotes are not commonly dropped and not commonly used since most poisons are slow acting and go away after a few seconds. Another way to remedy poison is to go to the town's magic user/potion seller; they will heal you and remove the poison effect.

Thawing potion
Removes the player from frozen/chilled status.