Not only is her choice of capitalization and the peculiarities of her y’s and T’s particularly pretty here, I thought it was an interesting choice to include a purple stone like amethyst in her characterization of the sun. The way the m’s start the creep in with this line (menaces, amethyst, moats, mystery) make me see sunset in a different light (NPI), sort of softer and even in different coloring than the glaring “E” of bright daytime light. And maybe that blending of the bright yellow light into the blues and purples of dusk and night are what this poem signifies, the softening of the sounds and colors as the sun sets on your reading.