age vs golden age

age and golden age both are nouns.

Word	Noun	Adjective	Verb	Adverb
age	Yes	No	Yes	No
golden age	Yes	No	No	No

As nouns, golden age is a hyponym of age; that is, golden age is a word with a more specific, narrower meaning than age:

age: an era of history having some distinctive feature
golden age: any period (sometimes imaginary) of great peace and prosperity and happiness

Other hyponyms of age include antiquity, Jazz Age, reign, turn of the century, literary period.

age (noun)	golden age (noun)
how long something has existed	any period (sometimes imaginary) of great peace and prosperity and happiness
a time of life (usually defined in years) at which some particular qualification or power arises	a time period when some activity or skill was at its peak
a late time of life
an era of history having some distinctive feature
a prolonged period of time