aged
alloy
aluminum
architecture
background
chain
concept
connect
construction
copyspace
design
diamond
dirty
floor
gray
grid
grunge
grungy
hard
heavy
industrial
industry
iron
ironworks
line
link
material
metal
metallic
old
panel
pattern
plate
rust
rusty
sheet
silver
solder
space
spot
stainless
steel
surface
template
texture
textured
tough
wall
weathered
work