I’m not sure if this was mentioned so forgive me if I have missed this topic somewhere, however something I’ve just noticed when using this rune.
“(6): +5% of toughness becomes condition damage.”
The following does not buff condition damage while using this rune.
Signet of Earth: Improves toughness.
Conjure Earth Shield: Conjure Earth Attributes: 180 Vitality, 180 Toughness
Stone Flesh (#5 trait in Earth Magic): Gain 1 toughness per level while attuned to earth.
Obsidian Focus (#10 trait in Earth Magic): Gain toughness while using a channeled skill.