OK looked it up, it was Albion wilde who posted it, here’s the link, the chair of Peter
https://freerepublic.com/focus/f-religion/4000440/reply?c=15
It sure is elaborate and beautiful, would like to see it in person
The chair is wooden, and it is set into that massive gilded bronze sculpture surrounding it. From the photo, it's hard to tell where the chair ends and the gilded bronze begins. It looks as if the chair may have also been decorated with gilding, who knows whether originally or at a later time. There is controversy, naturally, whether this chair is the original one (Wikipedia has more detail), but Bellini's handling of the symbolism—the Holy Spirit's descent upon Peter and the apostles, and Peter becoming the first "Vicar of Christ"—is powerful.