The Bauspiel Transparent Coloured Cubes add an extra special element to play. The see-through "jewels" in the centre of each of the 25 timber blocks allows children to discover light and the myriad of effects it brings: place them on a light table for a glowing array, near a window to shine a rainbow of colours over the floor, or look through them for a kaleidoscope view of the world.  
 
They are also the perfect addition to a building block castle or house, forming oh so pretty windows and portholes.
 
5 colours = yellow, red, purple, blue, green, with 5 cubes each
 
Part of the photo/video credit: @birnspiel, @kiko_502, @wander.mi.trio