How about a story showing a gold rush on a near-future colony of Mars?
Terri Main publishes a paper called "Science news for Sci-Fi writers," in which today I saw a link leading to an article from Io9 that shows a photo I'm including below:
This photo shows dry ice pits common in the southern hemisphere of Mars, a planet cold enough to fill these pits every Martian-southern-hemisphere-winter with frozen solid carbon dioxide from the Martian atmosphere. Every summer, some of the frozen CO2 (a.k.a. dry ice) melts away, revealing these pits with curious shiny gold rims. (For scale, the small one in the center is about 200 feet across.)
It so happens that as of now, no Earthly scientist knows what the causes the gold-coloring around these pits. What if it so happens that it's actual gold, that the process of forming and sublimating dry ice somehow brings subsoil gold up to the surface and deposits it along the rims of these pits?
If it should happen in the near future that human astronauts walk on Mars, something very technologically possible, the southern ice cap is about the last place they'll want to travel, due to a high elevation there that preserves a cold which by comparison makes Antarctica seem like cool summer day. But what if humans actually establish a settlement on Mars elsewhere and eventually someone gets around to exploring the southern icecap, and finds all this gold?
Martian settlers will first, of course, be interested in getting oxygen, food, water, and staying warm, but historically speaking, the quest for gold has had an fascinating effect on people. The settlers of Jamestown were far more interested in finding gold than planting food crops, a collective decision that led to the starvation of many of them.
Imagine human beings on Mars driven by goldlust, in fierce competition fighting it out in a place they can barely survive. for nothing more than lumps of cold precious metal...