The Dragon Crystalworking ability comes in 6 tiers. A new tier is earned every 20 levels. It is unconfirmed whether the tier of ability or the skill determines whether you can craft resources of a tier higher than your ability.
Dragon Crystalworking is most commonly used to craft Azulyte Crystals, which is then in combination with either Tri-cut Gems or Essence Orbs processed further by a Lairshaper to construct 2 Building blocks used in the construction of all lair chambers. To do so requires the use of a Crystalshaper and appropriate formula..
Dragon Crystalworking uses the Crystalshaping skill to determine crafting efficiency.