[SPAM] Potash: the key to Frit. imperialis
Arnold Trachtenberg (Wed, 07 May 2008 18:11:58 PDT)

Jim:

I have sought out Sulfate of Potash here in N. New Jersey after seeing
Ian Young's glowing praise of it. I was convinced to substitute Muriate
of Potash once but never again. I found the Sulfate of Potash and it
was manufactured by Espoma.

http://www.espoma.com/

I picked up something different last time and it was "Epsom Plus".
Listed as 0-0-22, derived from Sulfate of Potash Magnesia.

Arnold