Definition - What does Stonewool (Rockwool) mean?
Stonewool is an inorganic insulator made from stones or rocks by blowing a jet of steam through molten rock (such as siliceous rock or limestone) or slag. More advanced production methods involve spinning molten rock in high-speed spinning heads.
Stonewool can be used as a growing media for plants. For other purposes stonewool is chiefly used as a heat or sound insulator, or as a filtering material.
Stonewool may also be known as rockwool.
MaximumYield explains Stonewool (Rockwool)
Stonewool or rockwool is used in a wide array of applications and products due to its very high melting point and because it is an excellent insulator. It is often used for fireproofing, fire stops, and other temperature-sensitive applications such as cooking appliances.
Stonewool is a popular growing media for gardening and hydroponics because it holds water well and can allow air to circulate for plant growth. Its strength makes it suitable for root support.
The naturally high pH of stonewool makes it inappropriate for large-scale cultivation, but with proper conditioning its pH can be stabilized to make it suitable for plant growth.
The fibers in stonewool are abrasive and can release microparticles that can irritate or itch when in contact with the skin. Furthermore, stonewool should not be used in residential areas with high moisture levels (such as most basements) because fibers can absorb moisture and become a medium for mold growth.