Goldsmith
A goldsmith might have a wide array of skills and knowledge at their disposal. Gold, being the most malleable metal of all, offers unique opportunities for the worker. In today's world a wide variety of other metals, especially platinum alloys, also may be used frequently. 24 karat is pure gold and historically, was known as fine gold.
Valence electron
The most reactive kind of metallic element is an alkali metal of group 1 (e.g., sodium or potassium); this is because such an atom has only a single valence electron; during the formation of an ionic bond which provides the necessary ionization energy, this one valence electron is easily lost to form a positive ion (cation) with a closed shell (e.g., Na or K). An alkaline earth metal of Group 2 (e.g., magnesium) is somewhat less reactive, because each atom must lose two valence electrons to form a positive ion with a closed shell (e.g., Mg).