Koltose by Mash - 100% Natural River Stones For Painting are hand-picked and checked to ensure smoothness and the proper size for rock painting and arts n crafts. The size and shape of each stone will vary between 2? - 3.5? so you can be creative and create unique and special designs for each river stone. With a large smooth and non-porous surface you will find it easy and enjoyable to paint and design these rocks. Display your art in your home and garden keep a pet rock or hide them across the town and spread joy and positivity in your neighborhood. Makes a great gift too! Can be used in a flower pot garden painting rocks kindness stones etc. With thousands of ideas online you re bound to have a great time!