Unique Markings:

Grimm's loves wood because it is a natural material so it always has various markings that show up in their products, making each one unique. Grimm’s toys are always one of a kind, carrying unique marks made by nature. Wood grain has changing structures and colors which serve as proof of its natural origins. The unique variations are proof of quality, not defects. Discover the markings that make your Grimm’s toy Simply Unique!

From Nature:

Every piece of wood has its own appearance, its own character and its own vitality. Its natural characteristics, and unique markings are therefore always to be considered. For example, dark spots on the rainbow are caused by mineral deposits. This means that if the tree had grown further, a branch would have developed at this point.

Black stripes are also something completely natural. This is the so-called pith tube or "heart of the tree". It differs from the surrounding wood by the darker color and structure. When working on the wood, it can become completely or partially visible. This feature is part of the natural appearance of the wood. Therefore, these are not defects for Grimm's, but quality features of a natural product and as such are desired and welcome by them. We love this uniqueness of wood!