Exotic EG10-L02 Glass Pebble, Small, Black, 10 Pounds Glass is a "green" product, made from recycled glass that would be thrown away Made in the USA Non-toxic product, safe for Aquariums Glass pebbles 100 Percent recycled decorative glass Perfect for use in fireplaces, fire pits, or in decorative applications Available in Gray color Measures 1/4-inch to 1/2-inch