I usevermiculite for all my plants to make the soil for cactus and succulents, this is one of the best ingredients to add minerals and good drain to soil, as you can see at the bottom the table show how many minerals are found on vermiculite, very light weight.. this is a medium grain, just compare to the penny on picture to get an idea of the size.Medium Vermiculite (coarse) check the penny on picture to get idea of size of the grain Vermiculite and perlitehave been used for years to amend professional potting soils made from peat moss (called "soilless" mixes or artificial soils because they literally contain no soil). They also have been used in outdoor mixes, in turfgrass and outdoor plantings, for gardens, for special 100% perlite or vermiculite growing applications, and increasingly for commercial and amateur hydroponic growing and water conservation (especially in landscaping and gardening). Essentially vermiculite and perliteare used in the horticultural industry because they both provide aeration and drainage, they can retain and hold substantial amounts of water and later release it as needed, they are sterile and free from diseases, they have a fairly neutral pH (especially perlite which is neutral), and they are readily available, non-toxic, safe to use, and relatively inexpensive. As a rule of thumb, perlite tends to last longer, has a more neutral pH, and functions much better in hydroponics, outdoor applications, lawns and gardens (in part because it is stronger). Nevertheless, for decades they both have been used by professionals, dedicated amateurs and gardeners. Vermiculite is a member of the phyllosilicate group of minerals, resembling mica in appearance. It is found in various parts of the world, but currently the major mines are located in South Africa, China, Brazil, Zimbabwe, and the United States. The largest mine today is located in the Palabora region of North-Eastern Transvaal in South Africa. It's vermiculite is basically a hydrated phlogopite mica which has the remarkable ability to expand to many times its original volume when heated---a property known as exfoliation. Vermiculite: Unexpanded, Expanded and a Single Particle VERMICULITE TYPICAL CHEMICAL ANALYSIS ElementPercent by WeightSiO238-46AL2O3 10-16MgO16-35 CaO 1-5 K2O 1-6 Fe2O3 6-13 TiO2 1-3 H2O 8-16 Other 0.2-1.2 Chemical Formula: (Mg,Ca,K,Fe11)3(Si,AL,Fe11)4O10(OH)2O4H2OThe quantity is a full boxof 6 x 8 x 11 inch, about 8 dry quartsShipping for this items will be $9.95flat rate and can't be combine with other items. Sellers: Delight buyers. Get your own map of past buyers. Powered by eCRATER . List your items fast and easy and manage your active items.On Dec-27-11 at 21:45:27 PST, seller added the following information:Every buyer gets a MyStoreRewards invitation for cash backSellebrity Analytics