This item is created with Gnome Engineering (375); taught by trainers.
When it first appeared in the Burning Crusade expansion, this schematic required rather than Spellcloth. However, there was no such thing as Spellfire Cloth (it had been renamed to Spellcloth during the expansion's beta test), so it wasn't until the next major patch (2.1) that it was possible to craft this item.
However, many new epic-quality Engineering goggles were introduced at the same time that required only 350 Engineering skill to make and could be learned at any Engineering trainer, without any specialization required. These require to craft, limiting their quantity.
These Power Goggles requiring higher skill, specialization, and expensive materials - but no primal nether.