Akadama vs Turface vs Pumice

[JoBalz]

I have been reading a lot here about akadama, Turface MVP, and pumice. Lots of opinions have been expressed.
About a year ago I put equal volumes of each material in separate plastic jars and put them under my deck in the shade in central Oregon.
I opened them today, June 21, 2014. Photos are attached; akadama, pumice, turface in order left to right.
My estimate is that 99% of the pumice is intact, 95% of the Turface is intact, and 5% of the akadama is intact. The akadama was high quality and was purchased from a Japan-trained artist in Oregon.
Any thoughts?

A very interesting observation. Glad to see you backed it up with photos. I'm not surprised to see the result for pumice (a light-colored, extremely porous igneous rock that forms during explosive volcanic eruptions) as it's going to be far slower to break down than the other products. Same goes for Akadama, since it is a type of soil and not a rock, which is surface-mined, sifted and bagged, and supplied in various grades. Keep in mind, the deeper-mined grades of Akadama are somewhat harder and more useful in potting mixes than the softer, shallow-mined grades (meaning it's worth researching the brand before buying it).