They call it a 'sea shell'.
Faber's small green metal object is a two-way communication device that allows for covert communication between individuals. It resembles a seashell radio and is used in Ray Bradbury's novel "Fahrenheit 451" as a tool for sharing information in a society where books are banned.
The small green metal object in "Fahrenheit 451" is a Mechanical Hound, a robotic device used by the fire department to track down and eliminate those who possess books. The Mechanical Hound symbolizes the oppressive control and surveillance in the dystopian society portrayed in the novel.
In the book "Fahrenheit 451" by Ray Bradbury, Faber gives Montag a small metal object containing a concentrated form of a liquor called "Denham's" that can be used to sedate mechanical hounds.
The name Faber is of Latin origin, meaning "craftsman" or "worker in metal" which signifies someone skilled in a particular trade or craft.
the metal object becomes a temporary magnet
No one invented ferrous metal. It is iron (Fe) which is an element, this was discovered not invented.
[object Object]
In order to know what a metal object is on a dorm wall one would need more information. If a description of the metal object is given one may be able to determine what the object is.
Metals are not invented by anyone.
Metal plating.
Depends on what the "green" is. But I'd suggest a metal polishing compound.
in 1810
No one invented metal. Metals are naturally occurring elements in the earths crust (and core)