** UPDATE Please check out our Level 85 Tanking Gems post for updated info for Cataclsym! **
This list is made up of the Rare tanking gems available in Wrath of Lich King broken down by desired category and color. I am going by the following assumptions. You typically look for 3 things when looking for gems. Avoidance (defense), Effective Health (Stamina and Armor), or Threat (Strength, Crit, Expertise & Hit). What I have listed here are my recommendations for gems you should slot based on the color and going by the assumption that you want the socket bonus. There are many other gem combinations available and I encourage you to research and decide what is best for your tanking needs.
- Thick Dragon’s Eye – 27 Defense, jewelcrafter only, any slot
- Eternal Earthsiege Diamond – Meta – 21 Defense and 5% increased Shield Block Value
- Thick Autumn’s Glow – Yellow – 16 Defense
- Stalwart Monarch Topaz – Yellow or Red – 8 Defense and 8 Dodge Rating
- Enduring Forest Emerald – Yellow or Blue – 8 Defense and 12 Stamina
- Austere Earthsiege Diamond – Meta – 32 Stamina and 2% armor increase
- Solid Sky Sapphire – Blue – 24 Stamina
- Regal Twilight Opal – Blue or Red – 12 Stamina and 8 Dodge
- Enduring Forest Emerald – Blue or Yellow – 12 Stamina and 8 Defense
- Sovereign Twilight Opal – Red or Blue – 8 Strength and 12 Stamina
- Champion’s Monarch Topaz – Red or Yellow – 8 Strength and 8 Defense
Your choices for threat gems might instead include To Hit, Expertise and/or Crit, but I think it is too early to sacrifice opportunities for defensive stats to go with pure threat gems.