This 0.20 cu. ft. 10 lbs. 3/8 in. Black Decorative Lava Rock starts as molten lava heated from the depths of the earths natural volcanos. It is crushed down to a size of 3/8 in. and can be used in landscaping applications as well as in propane or natural gas firepits or fireplaces. Lava rock is the perfect material to be used for drought tolerant, water wise dry-scape landscaping and gardening. It will create a dramatic, natural effect when used in gardens, ponds and stream beds as well as around trees, walk ways, driveways and patios. These stones are easy to spread, protect soil from temperature extremes, restrain the growth of weeds and can also be used to help protect drainage areas from erosion.