There is a lot of superstition around mining fragments, or anything that involves venturing beneath the surface. After all, this small chunk of rock is all you've got, and no-one in their right mind would want to hurt it. The rewards, however, are great. Fragments are rich with valuable ore, and as varied under the surface as above.
Digging on fragments can uncover strange and wonderful objects:
Common earthlike materials that need processing and refinement before they can be turned into anything useful, common mineable minerals include:
A variety of strange materials can also be found underground. These include:
A green ore that releases a liquid when heated. This liquid has been found to consume almost all everyday materials.
A yellowish-purple rock that seems to secrete an oily black liquid. It feels nauseating and uncomfortable to look at.
A reddish ore from which blood can be extracted. It is soft and crumbly, unsuitable for building.
Bones found far underground, often forming complete skeletons. Nobody knows how surface-dwelling creatures managed to reach such depths without tools, and there doesn't appear to be any sign of tunneling.
WARNING! Explosive. Heat and Shock sensitive. Do not expose to direct stormlight.
Shards of strange, coloured glass buried far underground. They seem to posess strange refractive properties. The light doesn't scatter quite right.