The next one for me to have a go at was the Vinco tetrahedron - it is a really lovely 3 sided pyramid (obviously!) made from varicoloured Walnut. I really have a weakness for this wood so this was my personal preference but it was available in many other woods and a few are still available now. It is 64mm from apex to base and absolutely flawlessly made - you can barely see any joints at all. I did feel that I have enough coordinate motion puzzles and am pleased that this is just an assembly puzzle.
Having done the Vinco cube I had some idea what was required and just like the cube, the trick is to find out exactly where to place your fingers to pull it apart. However, it is a bit easier than the cube to open, once you do get the correct grip it is just a matter of pulling gently and it slides in half.
Overall a really nice piece for your ornament display and well worth a place in any puzzler's collection. Considering the workmanship it is worth the €55!!