5 Pounds - Clinoptilolite Zeolite Powder - Great CEC Exchange - High Potassium and Calcium Along with Many More Minerals and Elements - For You and Your Soil 5 pounds of Zeolite Powder with a pale green color by The Seed Supply Zeolite, which is of volcanic origin and contains the distinctive mineral Clinoptilolite, is an 85% opaline silica and is widely used as a soil amendment for it's ability to increase water retention in the soil and allow plants to more easily access it. Unbelievably, it can hold up to 55% of its weight in water and slowly releases it to the plant as needed. Great as a composting agent & odor/moisture absorbent This is used for external use only, DO NOT CONSUME INTERNALLY.