Sparks are unusual conjured items, as they last only few moments. When conjurer starts using such a spark (worn on \'floating nearby\' slot), it start floating around her, waiting for successfull hit of an opponent. And with first landed hit the spark bursts forth and explodes at the enemy, burning him a little. Conjuring sparks and wearing them all over again is what newbie conjurers do during combat when they have nothing better to do. As conjurers grow in levels they find another ways to spend their mana and time during combat, like recharging other conjured items or stabilizing them or whatever else. But sparks are fun at the low levels, and there are rumors about more powerful versions of this spell.