Beautifully designed and perplexing in nature, these 3-dimensional puzzles are a delight to both the mind and eyes. The glossy, vibrant pieces interlock to form sleek objects that are aesthetically pleasing enough to become decorations. Besides being entrancing in form, these puzzles are mind bending as well. My brother, an honors student in college, was at it for quite some time, and I never could figure out how to put mine together. Good for serious puzzle workers and people who like shiny things alike. In general, the number of pieces ranges from 37-49 for most puzzles with the more expensive puzzles containing more.