Ever wondered what perlite is or where it comes from? Us too! So, we decided to do a bit of research and what we found was awesome! FUN FACT: perlite is not a trade name, but a generic term for naturally occurring siliceous rock.

Perlite is a form of volcanic glass; but don’t be fooled, it is not like the others! After it is mined, it is heated in huge ovens until it ‘pops’ into a round, white material. This ‘popping’ feature and white color are what makes perlie stand out from those other volcanic rocks!

When perlite is heated to a suitable point in its softening range it expands. This is the cause of that distinguishing white color!
FUN FACT: the crude rock ranges from transparent light grey to glossy black, but the color of expanded perlite ranges from snowy white to greyish white.

Expansion happens because of the presence of two – six percent combined water in the crude perlite rock. Expanded perlite can be manufactured to weigh as little as 2 pounds/cubic foot making it adaptable for various different functions. Because perlite is a form of natural glass, it is classified as chemically inert with a pH between 7-7.5.

Now that we know what it is, let’s talk about what it is used for!
Perlite is used in more industries than just gardening!!
Here are the three main industries perlite is used in:

The first and obvious use for perlite is its horticultural use. It has a long and enviable record of performance as a propagating and growing media throughout the world. It has been successfully used in virtually all horticultural applications. Some being: glass house growing, landscaping, lawn and stadium turf and a number of container applications.

The next and not so obvious is its industrial use. Perlite is lightweight, non-combustible, and insulating and therefore is useful in refractory brick, high temperature insulation, molten metal topping, cryogenic insulation and much more!

The last general use for perlite is construction! Perlite and vermiculite have both been used for years as an aggregate in lightweight, insulating concrete and plaster. Also as a loose-fill-insulation material for concrete masonry blocks, cavity walls and residential homes.


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