"precious metal noted for its color, luster, malleability, and freedom from rust or tarnish," Old English gold, from Proto-Germanic *gulthan "gold" (source also of Old Saxon, Old Frisian, Old High German gold, German Gold, Middle Dutch gout, Dutch goud, Old Norse gull, Danish guld, Gothic gulþ), from PIE root *ghel- (2) "to shine," with derivatives denoting gold (the "bright" metal).
The root is the general Indo-European one for "gold," found in Germanic, Balto-Slavic (compare Old Church Slavonic zlato, Russian zoloto, "gold"), and Indo-Iranian. Finnish kulta is from German; Hungarian izlot is from Slavic. For Latin aurum see aureate. Greek khrysos probably is from Semitic.
From Homer on through Middle English, "red" often is given as a characteristic color of pure gold or objects made from it. This seems puzzling, but it might stem from an ancient practice of testing the purity of gold by heating it; in Middle English red gold was "pure gold" (c. 1200).
Nay, even more than this, the oftener gold is subjected to the action of fire, the more refined in quality it becomes; indeed, fire is one test of its goodness, as, when submitted to intense heat, gold ought to assume a similar colour, and turn red and igneous in appearance; a mode of testing which is known as "obrussa." [Pliny, "Natural History," 33.19]
dust n.
"fine, dry particles of earth or other matter so light that they can be raised and carried by the wind," Old English dust, from Proto-Germanic *dunstaz (source also of Old High German tunst "storm, breath," German Dunst "mist, vapor," Danish dyst "milldust," Dutch duist), from PIE *dheu- (1) "dust, smoke, vapor" (source also of Sanskrit dhu- "shake," Latin fumus "smoke").
Meaning "elementary substance of the human body, that to which living matter decays" was in Old English, hence, figuratively, "mortal life." Sense of "a collection of powdered matter in the air" is from 1570s. Dust-cover "protective covering to keep dust off" is by 1852; dust-jacket "detachable paper cover of a book" is from 1927.
To kick up the (or a) dust "cause an uproar" is from 1753, but the figurative use of dust in reference to "confusion, disturbance" is from 1560s, and compare Middle English make powder fly "cause a disturbance or uproar" (mid-15c.). For bite the dust see bite (v.).