Old Rear projection TV lens makes solar furnace

Old Rear projection TV lens makes solar furnace
Melting rock with a 36" fresnell lens

The local transfer station always has some old TVs.
I took some tools with me and stripped off the fresnell lens from a big rear projection set that had been sitting for a couple of weeks.
The corner was cracked, so I cut out the central portion and used some silicone to glue it into a steel mounting ring.
I mounted it to a tracking base, and did some experiments.
Wow this baby can generate some pretty high temperatures.
I started by melting a 3/8" hole clear through a 1/4" thick piece of lead in less than a minute.
Then I grabbed some stones and proceeded to turn them into lava. One must have had some stored gasses, so the molten rock made a beautiful glass bubble. Wonder what else I can do with this?