I published some time ago a "review" (actually it was more advertising than reviewing) about a puzzle made of concrete and magnets designed by Aaron Olivas and funded via kickstarter.
Aaron has started since some time the production of them and has shipped many. So now it's time to speak about the puzzle! ;-)
To remind you, the goal is to assemble the different pieces (that have magnets) in order to make a ball shape. The balls are available in different size, but I would recommand the biggest ball, because the medium ball (mine) is not so difficult. And the smallest ball may be even easier.
The puzzles are made of concrete, which is very unusual for making puzzles!! When you order yours, you can make different versions because you can choose the colors of the stains and of the glass pieces. So many many possibilities!! Actually you have 42 combo possible.
The finish is very handsome and very soft in the hands and the construction is pretty solid (does not fall apart) once it's completely assembled (the magnets are powerful enough).
The pieces have strange shapes and, in my opinion, are pretty original. Due to that and to the poles of the magnets you can make a "wrong" start. Indeed some pieces seem to fit together (because of the magnets and of the shapes of them), but then after you notice that you cannot do anything else with some remaining pieces. Thus, back to the starting point!
After you have started to assemble some pieces, then it's a bit "trial-and-error", and pretty straight forward: you try all the remaining pieces, if they fit or not. That's why I rank the difficulty as pretty easy. But, even given that, I feel it's a very nice and fun puzzle to play with!
You can also buy several orbs with different sizes and assemble them like the Russian dolls, but with always one piece not assembled, so that to be able to see the different layers. I think this can be very nice!
Now I need a base for the orb :-)
HERE you can see the kickstarter project in case you missed it, and contact Aaron if you're interested in purchasing any orbs!