With ropes guiding the way, we descend into crystal-filled chambers, discovering stunning formations, shimmering crystal clusters, and even rare, perfectly round crystal "puff balls." This is one ...

Generate Platonic solids, Archimedian solids, Catalan polyhedra, the trapezohedron, and some stellated polyhedra. You can also stellate any of the polyhedra, select polyhedra by their characterics and ...

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