What are the differences in ingress portal shield types?

I have collected a few different types of shields, with different colours and of differing rarity.

I assume the rarer shield types are more powerful in some way but I can't find any information on it.

Question : What different types of shield are available and what are the differences between them?

More detail, I currently have three shield types:

  • Green (Common)
  • Purple (Rare)
  • Pink (Very Rare)

When you select a shield to deploy in the Upgrade-menu, it actually shows you their different parameters (just like for resonators it shows how much the range would increase iff deployed).

The values for the shields are:

  • Common - MITIGATION 22(+6)
  • Rare - MITIGATION 22(+8)
  • Very Rare - MITIGATION 22(+10)

Of course it's a different matter to figure out how those values relate to burst-absorption.


New Shield mitigation (again)

  • Common - 30
  • Rare - 40
  • Very Rare - 60
  • Very Rare AXA - 70 (What is this?)

*Was 6,8,10 at first, later changed to 10,20,30, then to 20,30,50.

1 shield mitigation is 1% of reduced damage. The reduction is hard capped at 95%, though the mitigation can be higher than that.

*When the shield mitigation changed the first time, it was necessary to 'refresh' your inventory by dropping shields on ground and collecting them again. It is not necessary any more and all old shields should have the new values. For more informations read the following link.

What is the formula for damage mitigation in Ingress?