Roy wrote:

Somehow that just does not surprise me one bit. I deal with foundry on
a pretty large scale but only as a hobby or small side line business,
and patronize quite a few forums related to foundry stuff. One or
two forums will always find those wanting to use kitty litter because
its cheaper and they only want 5 pounds not 50 or 100.......but they
do not know what kind of kitty litter it is to begin with........They
all assume its one and the same, be it deorderized or plain jane
"western", and insist on usiing it for refractory mix, as well as
greensand molds.........Most of these folks only ever play with
aluminum or lead, and most will still run out and buy kitty litter and
then come back latter complaiining that their refratory or greensand
....

Roy, that's way different from using it in a pond. I'm sure the chemical
properties differ, but you were told the "physical properties are nearly
identical". In a pond, for planting purposes, or for sealing a natural
bottom, it makes little to no difference.
--
derek