Term: gold dust: the particles and flakes (and sometimes small nuggets) of gold obtained in placer mining
Broader: gold: a soft yellow malleable ductile (trivalent and univalent) metallic element; occurs mainly as nuggets in rocks and alluvial deposits; does not react with most chemicals but is attacked by chlorine and aqua regia | Unrelated: flash in the pan: someone who enjoys transient success but then fails