a common noun because it is a thing and common nouns include people, animals, places or things.
a concrete noun because it describes something tangible, something you can touch, it not something abstract like an idea.
It is NOT:
a proper noun because it is not a name of a person or place.
a compound noun because it doesn't consist of two or more words like, for example, <em>basketball.</em>
an abstract noun because it doesn't describe an idea or feeling, such as <em>happiness </em>or <em>freedom, </em>it describes something very concrete and specific.
a collective noun because it doesn't describe a group of things like, for example, <em>class </em>or <em>family</em>.