Photographing glass

So...how do you go about photographing something that is both transparent and highly reflective?

This is what I tried. I used a little table top collapsible studio thingy with a grey background draped at an angle - held there by the weight of the glass.

I need the glass itself to not be lit directly otherwise the edges would have disappeared. Instead I used a snoot pointing at the background and the subject was lit from behind. The glass edges now appear slightly darker than the background rather than just reflecting the light.

Canon EOS 70D, f/8 @ 135 mm, 1/250, ISO 100, No Flash