Step 1: Materials
some copper sheet (don't know gauge, just had some sheets laying around the basement so I used it)
various pliers/strippers/wire cutters
Step 2: Base
The base shown here was 2.5" x 2.5" by 0.3" when it was finished.
I used a vise to bend my first one, now I have a small metal brake I used for this particular one.
I didn't show pictures of how I folded it up, but it can be tricky sequencing the bends right.
One detail to mention is the 4 small tabs at each corner are meant to be bent so as the adjacent side folds over the tab. A little trimming of the tabs is required for the best fit - See the 2nd picture.
Step 3: Top
The top shown here is 2.75" x 4.9" (finished size) with 0.2" tabs.
I used a vise to bend my first one, now I have a small metal brake I used for this particular one and any cylindrical object I could find to give it the curve.
Step 4: Cut Wire
(4) 8 inch pieces
(2) 10 inch pieces
The (2) ten inch pieces are shown after they were bent
Step 5: Bending Wire
You can see the center of the spiral areas have small flat sections from being grabbed by the needle nose pliers. Round nose pliers eliminate this and make a more pleasing curve.
Step 6: Solder Everything Together
Some small clamps sure come in handy when putting it together.
It isn't pictured here, but I added a couple more pieces of wire to be able to hang the lantern.
All it needs now is a little RGB LED that changes color with temperature, but that's an instructable for another day.
Side Note: There is a whole science to getting a nice patina on copper, and a lot more colors achievable than the pale blue-green that generally comes to mind. Search around and check it out.