All pieces are 100% authentic. They are naturally formed by the wind and waves from the Devon coast. The photos show a representation of the sizes you can expect. All pieces will be approximately 0.5-1cm. I will make sure every bundle has a good variety of shapes and sizes. I have done my best to accurately represent the sea glass in the photos. If there is ever any problem with your order, message me and I will get back to you as soon as possible with a solution. Pease check my other listing for different sizes, shapes and colours.