Step 1: Recall the definition of amorphous solids.
Amorphous solids lack a long-range ordered arrangement of particles and do not have a sharp melting point.
Step 2: Analyze the given options.
Camphor, magnesium, and diamond are crystalline solids with definite lattice structures.
Glass does not possess long-range order and softens over a range of temperatures.
Step 3: Conclusion.
Therefore, glass is an example of an amorphous solid.