Pumice is a natural insulator. This is the unique property that separates pumice from all other chimney materials. 

The insulating properties of pumice allow the flue gases in the chimney to quickly reach their optimum temperature enabling the heating appliance to reach its optimum performance shortly after lighting. 

It also keeps the chimney warmer longer as the heat output of the appliance decreases - once again aiding performance and reducing the likelihood of condensation and soot build-up.
Why Pumice?
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The Isokern Standard Fireplace offers the complete look of a "traditionally built" masonry fireplace and more. First, all Isokern products are made of dense clean volcanic pumice which offers high insulation and lightweight componentry for quick installations. The fireplace is then lined with true brick for a custom look and then a custom finish to the owner's choice. Isokern is the perfect choice for interior or exterior installations where true masonry is required for longevity.
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