Question

why was the period of late 1800s known as “the gilded age”?
the gilded age was a time of glittering wealth on display as the rich gathered together.
a gilded thing was only shiny on its surface; beneath it was dark, worthless metal.
it was an era where the bright promise of the united states was being attained in abundance.
the california gold rush had resulted in ornate gold craftwork that was used in architecture.

Explanation:

The term "Gilded Age" was coined by Mark Twain and Charles Dudley Warner. It refers to an era of rapid economic growth in the late 1800s in the US. On the surface, there was great wealth and prosperity as the rich flaunted their affluence. But beneath this shiny exterior, there were many social ills like poverty, corruption, and labor - management conflicts. A gilded object is only shiny on the surface; underneath it can be of little value, which metaphorically represents the Gilded Age.

Answer:

A gilded thing was only shiny on its surface; beneath it was dark, worthless metal.