abstract
aluminum
ash
background
chrome
chromed
closeup
construction
dark
detail
dirty
galvanize
galvanized
grey
grunge
grungy
industrial
industry
iron
metal
metallic
old
oxidized
panel
pattern
plate
plated
scratch
sheet
shiny
silver
spot
stain
stainless
steel
surface
texture
textured
tin
weathered
zinc