That look like an Isamu Noguchi or one of his student functional sculpture.
If I recall correctly an insignificant sculpture of such size would fetch $3000-7000 during the 60-70s, and by the time the 80s came around his work fetch several folds over that of the 60-70s price.
I don't think it is affordable or practical for anyone of us mere mortals if it is indeed an Isamu Noguchi or one of his student piece.
If you can afford a piece like that you wouldn't be worry about the cold stone, because it is likely that floor underneath the stone is looped with heat pipes.