Metalborn
On Scadrial, metalborn was a generalized term for a user of the Metallic Arts, either an Allomancer or a Feruchemist[1]. A metalborn could use one or all of the 16 metals to access allomantic or feruchemical abilities. Rare Twinborn had both a feruchemical and allomantic ability, which may or may not have been in the same metal. Allomancers ingested their metal and then 'burned' it to gain their abilities while Feruchemists used metal to store a specific trait in which they could later draw out.
Notable Metalborn
Allomancers
Feruchemists
Twinborn
The Lord Ruler
The Lord Ruler was the only known Mistborn who was also a full Feruchemist, by Compounding he gained a great many astounding abilities, including his immortality.
Organisations
During the history of Scadrial, there were a few organisations of Metalborn, the Keepers for example were a group of Feruchemists during the Lord Rulers rule, while the Worldbringers fulfilled a similar role before the ascension.