It's a metaframe 6 foot long tank. Possibly either a restaurant/seafoot display tank or something. Bottom is glass, not slate. Stand is rough as a corn cob. Ridiculously thick glass, is a HUGE project but a mega cool tank that somebody wants, esp at this price.
I spent another hour today wondering if I could do it. I'd certainly have to build a new stand for it, the metal stand would put all one hundred bajillion pounds of it's weight on four tiny little metal feet, which would punch right through my floor. I mean, it's gotta be 125 gallons minimum, probably more like 150? They'd take $80 to be rid of it for sure.