"Listen In" sounds like an acid-rock song filtered through bright pop sensibilities.

NPR: Falcon: 'The Sandfighter'

Mr. TOM McCOLLOM (Geochemist, University of Colorado): The sulfate salts that are in there come from reaction of the rock with sulfuric acid rather than from evaporation of a fluid.

NPR: Mars Rover Marks Second Anniversary of Landing

Hydrochloric acid was once used to retrieve metals from rock, but many firms abandoned it for cost reasons for cyanide.

FORBES: Firm Uses Cyanide--Free Method To Leach Gold, Other Metals

The acid observation from Labour MP Don Touhig that Plaid were "running rings" round Labour in government was pretty much rock bottom.

BBC: State of Play 4 - Labour