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PERLITE- Large Grains (Horticultural-Size). 2500°F (Lg Bags)

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Perlite is white, light, strong, exploded volcanic rock in tiny spheres that can handle up to 2500°F making it popular in many creative recipes folks use requiring natural, lightweight insulating materials with incredible heat tolerance.

It's a white-light, miniaturized version of volcanic rock popcorn.  Perlite comes in BIG but not heavy bags., though as tall as a 5-year-old they are only 22 lbs.

This LARGE GRAIN PERLITE, commonly referred to as 'HORTICULTURAL PERLITE', though we also have lots of SMALL Grain CASTING Perlite (less than half the size).  It's perfect for blending with castables.  The smaller size is more of a specialty and its harder to source.  Though both sizes can be used for gardening, traditionally many folks prefer the large grains for Horticultural applications. 

The smaller grains are optimal for mixing with concrete, plaster, gypsum, hydro stone, and especially refractories because they impart lightness and bulk while maintaining more strength than larger Horticultural-sized Perlite when casting.

Both sizes are also commonly used on their own beneath forms, as a component to a packable base, or between layers.  It can be used to fill the spaces in some pizza oven designs, in combination with, or instead of refractory wool.  Its thermal efficiency makes it popular in some pizza oven designs allowing exterior finishing with high-character traditional architectural bricks to be protected from the firebox.

We'll have some builds utilizing this build style on display soon.

We are doing some experimenting and we will have some refractories available premixed with perlite to make fun projects like backyard rocket stoves more affordably than with 100 percent refractory cement, but for now, it's available on its own for you to mix yourself.

22 lb. Bags

Made in Canada


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