Dark field imaging - what would be a good sample?

[daveyman]

I am doing a lab for my optics class. My group has chosen to set up a simple dark field imaging device using a HeNe laser. My question is this: what would be an easy sample to image? Something that is common and easy to find but that would also produce a nice dark field image?

 

[Andy Resnick]

Try a slab of plastic (like polycarbonate or acrylic) with some light scratches- safety goggles (not for the HeNe!) may be a good place to start.