Silver and Gold belong to a special group of metals known as the native metals. They are found naturally on their own and not in combined form in rocks.
These metals are found uncombined because they are unreactive.
They prefer to alloy with themselves.
Calcium and magnesium on the other hand are reactive metals.
The unreactivity of these metals makes them uncombined in nature.
Energy may exist in different forms such as potential energy when a body is at rest, kinetic energy when the body is in motion, etc.
Energy can neither be created nor destroyed, however, it can be transformed from one form to another. For example, chemical energy may be transformed into mechanical energy or other forms of energy.