Dwarves

While goblins are engineers, dwarves are architects obsessed with few things. Among them, metal and stone. These creatures, derived from the Plane of Earth, have an exceptional power to shape and communicate with these two materials. Their innovations are still surprising even with these skills; after all, not everyone is capable to discovering the nearest tunnel by touching the floor in a certain way, or slowly liquify a block of stone like it was clay.
Their affinities make many of them choose to build large lairs underground, at times on mountains, or just under another community, living one or two lives without the full knowledge of those on the surface.
Dwarves are great architects, possessing an instinctual understanding of structures, stability, and a unique visual flair in their marks upon stone.
Dwarves can frequently be seen by other individuals as mountains, resisting the changes to the world around them with an endless stubbornness. They enjoy storing history away, always looking back; when parts of their communities decide that an aspect of their tradition needs to change, however, they are capable of bringing about great changes to the fields of philosophy and science. Dwarves were the first to discover the secrets of Space and Time hidden in Dunamancy when trying to combat the effects of erosion on their great temples; they learned the great magic Runes of Giants and resisted their changes, and... Dwarves were the only people outside of the [REDACTED] to [REDACTED] by themselves.

Ravik's knowledge as given by DM:
Ravik knows two things. One, dwarven bones aren't made of calcium- they are usually made of one solid metal, due to their elemental heritage. Two, in the decades after their arrival to the material plane, some dwarves began being hunted as sport for the metal in their bones, before this practice was completely criminalized and faded into history.
By completely criminalized I mean groups were set up to protect dwarven communities, raids on known hunters happened, etc