These highly tactile cobbles are wonderful to touch, feel and examine. They are smooth but not entirely see-through, so they are translucent rather than entirely transparent. When placed on a desktop, they look lovely, but when used on a light panel, they catch the light, and the colours look even brighter. They can be used for colour mixing, pattern making, and creating simple pictures.
 
They come in 6 distinctive colours - yellow, red, blue, green, orange and purple, and each set contains 6 different-sized cobbles from large to small. The large cobble is 85mm across. Shapes are asymmetric, making them useful for artistic picture making as well as necessary for the development of better mathematical language, such as "larger," "smaller," "medium," "tiny," "curved," "below," "above," "similar," and "different."
 
With care, a set of six pieces can be balanced on top of each other to create a small stack, but this requires great care and patience, which helps improve hand-eye coordination and fine motor skills. With so many uses, every classroom should have at least one or two sets of these. Pieces come in a screw top jar for easy access and storage after use.