cat litterI

Here in New Zealand, I have been unable to find a local variant of the afore-mentioned Turface, or other calcined clay.
The local version of kitty-litter [kitty-sorb etc] is actually zeolite - directory to wikipedia here:
http://en.wikipedia.org/wiki/Zeolite , and the FreeDictionary definition :zeolite
Any of a family of hydrous aluminum silicate minerals, whose molecules enclose cations of sodium, potassium, calcium, strontium, or barium. Zeolites are usually white or colorless, but they can also be red or yellow. They are characterized by their easy and reversible loss of water of hydration. They usually occur within cavities in basalt.
and a 'link' to a NZ supplier of zeolite : http://www.moutere.com/zeolite
"Zeolite is thermally altered clay that is quarried from an area near Rotorua in the North Island of New Zealand. It is dried, crushed screened and bagged into a range of particle sizes. ...Potting mix additive; improves water retention and enhances nutrient transfer."
It is also mentioned as an additive in potting mix in the following 'Encyclopedia of New Zealand':
http://www.teara.govt.nz/EarthSeaAndSky/MineralResources/RockLimestoneAndClay/10/ENZ-Resources/Standard/1/en
Altough I haven't used it as a substrate on its own, I have been adding a proportion to my sifted bark/ gravel/ sharp sand for a couple of years. The main reason I haven't used it alone [although I have heard of at least one person who has], is because it is basically off-white in colour. However, it aleviates the monotonous grey of our local Greywacke gravel.