Turface

From BonsaiWIKI

Turface is the brand name for a type of fired, calcinated clay that is produced by Profile Products LLC for use as soil conditioners and top dressings for play fields.

Turface MVP is a preferred grade of Turface because it contains fewer fines, but will still probably require sifting or washing prior to use in a bonsai soil

Bonsai Soil Components

Inorganics: Shale | Sand | Haydite | Turface | Ceramis | Oil-Dri | Decomposed Granite | Kitty litter

Volcanic: Pumice | Perlite | Vermiculite | Lava

Japanese Soils: Kanuma | Akadama | Hyuga

Organics: Fir bark | Redwood bark | Peat Moss | Coir | Muck | Charcoal | Compost | Field soil | Potting soil