How are Bender cobblestones size graded?

Benders offers two different sacks of cobblestones. In one of these, cobblestone size is 70 – 100 mm. In the other it is 100 – 250 mm. Cobblestones are size graded in machines. The stones are screened through large meshes that separate the different sizes. Because the cobblestones are not totally round and are a product taken from nature, sizes can vary.

The design of the meshes means that stones can fall through if any one side matches the size criteria above. Thus, depending on stone shape (dimensions), sacks may contain different grades.