This is an original CMY Icosahedron.
CMY stands for Cyan, Magenta and Yellow, (also known as RYB for Red Yellow Blue) are the three subtractive primary colours in life.
An Icosahedron is is a 20-faced polyhedron containing 20 triangular faces, with 5 faces meeting around each vertex.
You can rotate the Icosahedron or change the angle from which you're looking at the it and you'll see different colours coming to life. And depending of your environment you're in, you will discover endless different and new colours and shades. This is called subtractive colours mixing.
As it is a more complex shape than the cube, the possibilities of mixing and finding new colours are even greater...
The size is 50*50*50mm
