Black Powder

Originally the creation of Mindan Jijor, a dwarf engineer, the powder obtained quick popularity and spread due to its various uses in mining, allowing for faster digging, rubble clearing and gallery creation.
The original mix used was composed of six parts sulfur to six parts saltpeter to one part birthwort herb. This formula was later improved upon and made more reliable, leading to it being used in the creation of focused explosives and other warfare-inclined machinery.
It is said that the powder alone is credited with the survival of the dwarven race against the dark horrors they faced during their collapse.
  Despite the collective efforts of the dwarves to guard the formula and way of creation, the powder itself eventually spread to the rest of Eidos, albeit in low quantities due to the black markets that reside within the dwarven strongholds. From the year 260 onwards repots have written about finding the black substance, with other dwarven prototypes to be used in tandem with it, as far south as Greenwall.

In current time, besides the uses in mining, the dwarves have refined and learned from blackpowder to the point of being able to create hand-held devices, nicknamed boom-sticks, able to use the substance to shoot small metal pellets at incredible speeds, making it a deadly ranged weapon.
On a lighter note however, the gnomish counterparts of the dwarven engineers managed to transform the powder into a visual display by combining it with various other chemicals to add shades of colour to the explosion that follows after the powder was shot into the air. A creation they have aptly named: Fireworks and which saw wide-spread success with carnivals and festivals all over the known world.