The devs told us exactly how WoD weapon enchants work at the link below.
http://us.battle.net/wow/en/forum/topic/13087818929?page=23#442
I'm pasting it here in case they retire the beta forums after release.
Mark of Blackrock
Grants 500 Bonus Armor for 12sec.
100% chance on deal/take any damage, 40sec ICD
Effect can only occur when you are below 60% health.Edit: Changed to 100% chance at 60% health threshold.
https://twitter.com/WarcraftDevs/status/543261642599845889
Spell
Mark of Blackrock
Physical
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Patch 6.0.3 Hotfixes: November 25
Mark of Blackrock now requires 3 Temporal Crystals (down from 15) and 5 Scorcerous Earth (down from 10).
Related Buff: [spell=159679]
Tooltip
Permanently enchants a melee weapon to sometimes increase Versatility for 12 sec. Effect can only occur when you are below $m1% health.
Cannot be applied to items above level $ecix.
Spell facts
Datamined from the current retail build. Numbers that scale with level or stats are shown at their base value.
Reagents
Items that grant this spell
More Enchanting spells
Related
Community notes from Wowhead · 8 comments
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