plate
A "Layer" is a flat covering or thickness
cool solid rock
Another layer of a pyramid scheme
Enameled metal is often referred to as enamelware. It is metal cookware or accessories that have been coated with a layer of enamel, which provides a smooth and durable surface as well as added color and design options.
The outer covering of the grain is called Husk.
The outermost layer of the Earth is known as the crust.
ganglia
It is called the enamel. It's the most external layer of a tooth and the hardest substance in the body.
im only 13 so don't complain if I'm wrong but, to my believe it's simply known as a compound or mettalic-compound......could call it metal-metal.
testa
scales
You call someone that studies metal a metallurgist.