Is sapphire a common noun or a proper noun?

Answer 1

Sapphire is a common noun. A common noun refers to a general, non-specific person, place, thing, or idea. In this case, sapphire is a type of gemstone, and it does not refer to a specific or unique sapphire but rather to the general category of blue gemstones.

Answer 2

It can be both. If it is capitalized, it is someone's name and thus a proper noun. If not capitalized, then it is the gem stone and is a common noun.

Answer 3

Proper noun