In a town near the Golden Gate, dust is constantly blowing through the air, except when sea-fog settles it. As a child, the speaker was told that some of that dust was not ordinary dirt but gold. At sunset, the wind-blown dust really does look golden, so the idea feels both fanciful and almost true. The repeated line about being “one of the children told” captures the way a child receives a story—accepting it with wonder rather than doubt.
The closing image turns that golden haze into something sterner: life near the Golden Gate is described as gold dusting everything people eat and drink, and the children are told “we all must eat our peck of gold.” The mood is wistful and slightly ironic, mixing a child’s sense of magic with the adult recognition that every place has its grit to swallow.