Cinder Stones

During the Ancient Era, people didn't use peat, wood or coal to heat their homes. When the power of the gods still surged through Vanelle, they had access to Cinder Stones - a type of material which could be mined from an abundance of sites throughout the Parede Mountains. While they did not evoke cinder in their appearance, when exposed to fire, they would quickly heat up and keep that heat for many days. It is believed that this was due to a blessing from Hem, the god of hearths and homes.
The cinder stones would be placed in strategic places throughout people's homes, where we may today have fireplaces, for example, and would keep them warm even in the coldest of winters. These stones were so prevalent and so readily available that it is believed people built them into the walls of their houses, in place of insulation. They were also used for cooking. Depending on how long they were held in a fire, the cinder stones could become incredibly hot - hot enough to boil water or heat a skillet, without a doubt.
Sadly, around the start of the first era, when the gods had well and truly left Vanelle to its own devices, their effects on the world also started waning, and the cinder stones were no exception. At first, people started noticing they were not keeping warm for quite as long, didn't get quite as hot no matter for how long they were exposed to fire, and during harsh winters it became harder and harder to keep homes at a comfortable temperature.
Eventually, the cinder stones were nothing more than regular rocks; the poser Hem had imbued them with had left, just like him. The transition to other heat sources was fraught. The fact that people had to start burning fuel in their homes led to countless fires and quite a bit of remodelling - chimneys had gone out of fashion and just weren't put into houses built during the ancient era.
Vanellians have now adapted to modern fuels, and are coping expertly with the associated challenges, but one can't help but wonder how the world would be different had the cinder stones still held their power.

Type

Stone

Color

Black