Been usin it for years with zero issues, know lots of growers usin it
Must be either baked or another form of bentonite. Or conceivably I did something else that killed the plants. Pretty sure it was the kitty litter though.
Actually I just found a page that said American cat litter is usually montmorillonite, about which wikipedia says "Chemically, it is hydrated sodium calcium aluminium magnesium silicate hydroxide (Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2·
nH2O. Potassium, iron, and other cations are common substitutes, and the exact ratio of cations varies with source." What I had really was sodium bentonite. It said on the package or I looked it up or something.
Now I looked up bentonite on wiki and it said;
"
Bentonite is an
absorbent aluminium phyllosilicate clay consisting mostly of
montmorillonite. It was named by Wilbur C. Knight in 1898 after the
Cretaceous Benton Shale near
Rock River, Wyoming.
[1][2]
The different types of bentonite are each named after the respective dominant
element, such as
potassium (K),
sodium (Na),
calcium (Ca), and
aluminium (Al). Experts debate a number of nomenclatorial problems with the classification of bentonite clays. Bentonite usually forms from weathering of
volcanic ash, most often in the presence of water. However, the term bentonite, as well as a similar clay called
tonstein, has been used to describe clay beds of uncertain origin. For industrial purposes, two main classes of bentonite exist: sodium and calcium bentonite. In
stratigraphy and
tephrochronology, completely
devitrified (weathered volcanic glass) ash-fall beds are commonly referred to as K-bentonites when the dominant clay species is
illite. Other common clay species that are sometimes dominant are
montmorillonite and
kaolinite. Kaolinite-dominated clays are commonly referred to as tonsteins and are typically associated with
coal."
I don't know. I just know I personally won't be using kitty litter in a medium.