Completely unaware of Lith’s inner turmoil, Professor Nalear continued her explanation.

“Red, orange and yellow are classified as low grade crystals. These crystals are the most cheap and common. They hold the smallest amount of mana and once it’s consumed, they crumble to dust.

They only have a limited number of uses as mediums for Wardens’ and Alchemists’ most simple creations, while they are useless to Forgemasters.”

– “Cheap?” Lith was stunned by Nalear calling something worth dozens of gold coins cheap.

“My staff runs on a red crystal, and so did Yurial’s array during the second exam. Even he was reluctant consuming one. I’d better ask him for explanations later.”–

“For example, red ones can be used to prolong the duration of an array or to grant its control to someone different from the caster. In the former case, the Warden places the crystal inside the formation, giving it an extra mana reserve.

“In the latter one, the Warden sets his imprint on the crystal while conjuring the arrays. This allows whoever holds the crystal to turn them on and off. Red crystals are considered to be ‘dumb’, since despite being imprinted, anyone can use them, even against the Warden’s will.