Wollastonite, a natural calcium silicate mineral, is unique among soil amendments as a source of silicon and carbon-neutral calcium. Wollastonite is a naturally occurring mineral that is a chemical combination of calcium, silicon and oxygen. Wollastonite is formed when limestone or other high-calcium rocks undergo high temperature and pressure changes sometimes in the presence of silica-bearing fluids such as in skarns or contact metamorphic rocks.
Wollastonite is a naturally occurring, calcium metasilicate with the chemical formula
Wollastonite is made by crushing, drying and milling the wollastonite ore. The same ore is used for all grades, which differ only in particle size distribution. Wollastonite is not contacted by flotation chemicals or chemical treatments of any kind. Because it is milled natural ore, elemental analysis can show natural minor variations. It is Mined in the USA and Mexico.
- High brightness
- Low moisture and an oil absorption
- Low water solubility
- High pH
- Low volatile content
- High melting point
- Medium hardness (4.5 on Mohs’ scale)
- Thermal stability
Wollastonite contains Calcium Silicate and is used as an multipurpose soil amendment that helps crops resist powdery mildew disease, supplies plant available calcium and silicon, and serves as a substitute for agricultural limestone.
For best results, apply wollastonite according to soil test results and agronomic recommendations. Application rates will vary according to plant requirements and soil conditions. Consider soil/media pH as well as calcium and magnesium requirements in addition to silicon supplementation when using this product as part of a balanced fertility program.
Greenhouses/ Soil Less Mixes:
Add 1 to 2 pounds of wollastonite per cubic yard of the soilless mix, or enough to adjust the pH of the media into the desired range. Please monitor PH 1-2 weeks after application to determine the rate of PH adjustment and then adjust application rate accordingly.
Market Gardens/Field Vegetables:
Spring or fall application; incorporation is recommended. Apply at 1.5 to 4 mT/ac. Sandy soils, soils low in organic matter; cucurbits and brassicas will respond to higher rates.
- Agricultural Technical Sheet including list of scientific studies
- Spec Sheet
- We can fit 50 x 50 pound bags on a full pallet
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