Rifny Pebbles for Fish Tank Flower Pot Decorative Stones Small Natural Crystal Agate Gravel for Succulent Cactus Terrarium DIY Flower Pots Decorative24 Oz (Blue, 0.7-1cm). Weight: approx. 680 g. Natural river chippings are mainly used as top dressing for small plants such as succulents.
eBay