1/4"- 1/32" Black Natural Cascade Mountain Volcanic Lava rock for use in soil mixes for Bonsai, Succulents, Cactus, hydroponics and soil mixes for specialty nursery plants. Also for top dressing bonsai and terrariums. Available in 15 Oz., 10 Cups, 5 Quarts, 3 and 6 Gallon volumes. 15 Ounce quantities are shipped First Class, all other quantities are shipped Priority Mail. - Our 10 cup box will fill 1 1/3 trade gallon containers. - Our 5 Quart box will fill 2.5 trade gallon containers. - Our 3 Gallon box will fill 6 trade gallon containers. - Our 6 Gallon box will fill 12 trade gallon containers. Pleasing black color. This lava is very hard. Most particles are 1/4", with a few down to 1/32". Neutral PH, doesn't rot, all natural, relatively light weight and porous. First photo shows our 1/4" - 1/32" black lava dry, the second photo shows the lava wet. Our lava is hand packed and bagged with a reusable tie for easy storage after you have used part of the bag. If your lava dries before using, moisten it to keep dust from forming. Dust from any rock or potting soil product should not be inhaled and can be irritating for people with sensitive lungs. Scenic Hill Farm is a licensed Oregon nursery -- license # L0170090NG