What does “woman as gold as the river bottom” mean? new orleans by joy harjo

This short excerp from Joy Harjo´s poem " New Orleans", is a metaphor, which basically describes the futility of following impossible dreams or trying to achieve something that will never be yours or that simply,is out of your reach, no matter how stubborn you might be and no matter how much determination you have, you will never reach it, so dancing with a woman as gold as the river bottom also represnts the persistance of Spanish explorer Hernando DeSoto who died trying to find and conquer a big empire as he had witnessed in Peru.