what next

my defense rating is 485 is that the cap? What is the cap?

Once you have reached the defense cap what kind of gems should a tankadin be looking to get..

Before someone responds rudely, you still want 490 Defense to be uncrittable in raids. As far as gems, you should probably stick to stamina and use defense gems if you're below 490. For threat, use strength gems (although you shouldn't need to).
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Moduspwnens - Shattered Hand

Modus has it on the nose.

There are many, many stickies that cover this, and probably most of your gear concerns already.

Check the Basic Training, Advanced Training, Gear Questions and Advice, and WotLK forums.
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Official thread killer

There is no "cap" by the way. There's a minimum you want to be uncrittable (that being 490), but the more defense the merrier (I have 520 or so).

After you hit 490 you may want to go Stam.
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