Perlite and vermiculite are mineral rocks frequently crushed and used in home and commercial applications. Each rock has its own beneficial use. Perlite and vermiculite both expand when heated and are porous and lightweight. Vermiculite holds water easily, while perlite allows water to drain through it easily. Both are widely used in horticulture.
This rock, with a number of minerals within it including sodium, aluminium, calcium, and magnesium, resembles mica in its unexpanded form. Typically, vermiculite is expanded for use through heat application. The expansion process turns vermiculite from a flat, shiny rock to a porous, thin wormy appearance. The name for vermiculite is derived from the Latin for 'vermiculare,' which means "to breed worms." This rock is mined in South Africa, China, Brazil, Zimbabwe and the USA.
Uses of Vermiculite
The most well known use of vermiculite is in gardening. Vermiculite traps water in its porous surface. Mix vermiculite into the soil to help it hold water for plants. It is also used in pool bottoms with a mix of concrete. A pool liner is placed on top of this bottom to finish off the pool. Vermiculite also serves as a packing material in industrial settings.
This rock mineral also expands when heated. It pops like popcorn in high temperatures due to its water content. Perlite consists of mostly silicon, aluminium and potassium. In its natural form, perlite is a greyish-blue, compact rock with shiny spots. When expanded, it is whiter in appearance, lightweight and slightly porous. The white colour of expanded perlite is its most identifiable characteristic. Perlite is mined in Greece, China, USA, Japan and Turkey.
Uses of Perlite
Like vermiculite, perlite is commonly used in gardening. Where the former holds water in the soil, the latter is used to increase drainage of compact soil. These porous, lightweight particles allow the water to drain through them and loosen soil, making it easier for plant roots to grow. In construction, perlite is used as loose insulation in masonry and concrete blocks. It is fire resistant, so raises the fire ratings of structures it's used in. It is also used in cement, as filter material for aquariums and ponds, in food products and as an abrasive for soap and polish.