I made this to donate to the the Hyde Park Art Center, which I did, and someone bought it. The steel is 3/8" thick. I drew the pentagram with a compass and a ruler according to a formula. I think I used some sort of a dremel to grind the pictures into the steel. Shit, I forgot the crystals. These are Swarovski crystals that I got from the ultra-flexible Terri Smith. I drilled the insets and used super glue to set them. I love how the 5 screws leave a star in the wall.
From what I remember, it's about 20" across.