This is the 12050th most frequent Russian word.
золотых
"Золотых" means "golden" or "of gold" in English.
Here, 'золотых' is the genitive plural form of 'золотой', meaning 'gold' or 'golden'. It is used to describe the material or nature of the coins.
У него есть коллекция старинных золотых монет.
He has a collection of antique gold coins.
In this sentence, 'золотых' is an adjective in the genitive plural form, modifying 'years'. It is metaphorically describing an ideal or cherished time period.
Это был момент моих золотых лет.
This was the time of my golden years.
Here, 'золотых' describes the shades of the sky with a possessive or qualitative attribute, again in the genitive plural form.