First seen in this film, ADA has released the Unzan Stone. In a nutshell, it is a processed volcanic stone with indented rough surfaces. The stone is available in small, medium and large sizes and is recommended for use in an iwagumi aquascape.
Another use of the stone is to implement ADA’s recent trend in growing wabi kusa in the hollows of their stones. Unzan is an ideal candidate for this use.
One of the highlights for us for this film was the chopping of moss to reduce them to a small enough form to be placed naturally on the Unzan rock. The end effect of having moss grow outwards over the rocks is simply tranquil, giving the rocks an aged look.
[TAG]
[T A G] 
Really an impressive video again by the master himself. The surface of the stone really resemble lava rock, but of course the black/grey color of Unzan has more striking contrast for the plants to grow.