In the sentence.........His hair is the color of shimmering gold.........what part of speech is gold? The teacher said it was an adjective but I believe it is a noun

I agree -- if that is all of the sentence, then "gold" must be a noun. It's the object of the preposition "of" -- and therefore must be a noun or pronoun.

However, if the phrase is something like this -- "of shimmering gold coins," then gold is an adjective.

What is the entire sentence?

That was the complete sentence. The odd thing is she said both shimmering and gold were adjectives. Even if she believed gold was an adjective, then shimmering would be an adverb as it modifies the 'adjective' gold. Of course what I had was shimmering (adj) and gold (noun)

Thanks for the additional information. I guess we all have "brain farts" and bad days. <g>

To determine the part of speech of a word, it's important to understand its function and how it is used in the sentence.

In the sentence, "His hair is the color of shimmering gold," the word "gold" can be considered both a noun and an adjective, depending on how it is interpreted.

If we consider "gold" as a noun, it functions as the object of the preposition "of" and represents the substance or material that the hair color resembles.

On the other hand, if we consider "gold" as an adjective, it describes the color of the hair, modifying the noun "color." The word "shimmering" further emphasizes the adjective, providing additional descriptive information about the color.

To determine whether "gold" is used as a noun or adjective in a specific sentence, it is helpful to ask yourself the following questions:

1. Does "gold" represent a substance, material, or object? If so, it is likely functioning as a noun.
2. Does "gold" describe or modify another noun in the sentence, such as the color or quality? If so, it is likely functioning as an adjective.

In this case, both interpretations could be valid. Given the context provided, the teacher's determination of "gold" as an adjective may be based on its descriptive function in modifying the noun "color." However, it's worth noting that "gold" can also be the noun representing the material or substance itself.