Drowcraft

A drowcraft armor or weapon was one that was, as the name suggested only possible for drow to make.

Benefits
A drowcraft armor or weapon worked like a +2 armor or weapon in an area of faerzress or inside an earth node in addition to its other enchantments. Its real beneficiary though wasn't the user but the creator.

Creating magic armors and weapons was a costly affair. A drowcraft armor or weapon was crafted while using the costs usually needed for a +1 armor or weapon but worked like a +2 armor or weapon.

Disadvantages
A drowcraft armor or weapon had a number of disadvantages built in.

Such a weapon was powered by faerzress  oran  earth node  and thus lost its magic outside of such an area. Furthermore, these kind of tools were very weak against sunlight. Exposing them to it, even indirectly like in a room or even in a scabbard,  could lead to instant disintegration of them. Apart from not exposing them to sunlight, drowcraft armors and weapons could be kept safe inside a lead-lined container (indefinitely) or by coating an armor or weapon with darkoil, though only temporary.

Reputation
A  drowcraft  armors and weapons were quite popular among drow in the Underdark. But by 1372 DR, such weapon stopped to be popular in a few drow cities, while in the case of armor, the fall from popularity was more widespread.

Crafting
To craft a drowcraft armor or weapon, the crafter needed to be a drow capable of casting contingency and disintegrate.

Notable Ones
Weapons:

Drow mission blade

Hand spinneret

Queen's scourge