Gnome

Here's my take on a Gnome, the little subterranean humanoid being which was first mentioned by the alchemist Paracelsus (1493-1541) as the elemental of earth. Gnomes are born through spontaneous generation in the bowels of the Earth, do not measure more than 40 cm, and have the power to phase through earth and rock as humans go through air. They have perfect knowledge about ores and precious stones, which is why alchemists seek their services. Sometimes they're described as taciturn, and sometimes as friendly and docile.

Through the ages, their role as the elemental of earth faded from collective imagination, and they became more and more similar to the dwarves of European folklore (themselves being spiritual descendants of the Dvergars from Norse Mythology). Eventually, they ended up becoming smaller cousins of the dwarves in modern Heroic Fantasy universes, despite the differences between the two original concepts.