Re; messages 230- 3 (Bev Tall) and -4 (Ray Bark) "a rock made out of DE "? I don't wish to be pedantic but diatomaceous earth (DE) or diatomite IS a sedimentary rock, sometimes unconsolidated and, when dry, a powder. Something synthetically "made out of DE " is, by definition, not rock!
Ray Barkalow's contribution may explain the process referred to by Bev in that the "calcined muds" could be diatomaceous earth artificially heated (calcined) to dryness and possibly fusion. Just in case there is confusion, 'calcination' implies no essential connection with calcium or lime(stone) although lime and other minerals are often 'calcined' (lime burning) just as silicous diatomaceous earth can be! Another pedant might explain the derivation of 'to calcine' and how its 'calc' root became divorced from calc-ium! (Maybe alchemists used the term before mineralogists got in on the act!). For orchid use, are the essential properties porosity and, for all practical purposes, inertness? DE is also a wonderful physical water filtering medium because each 'skeleton' is a micro-net cage. John Stanley > (Message 3 -The potting medium you are thinking of is a rock made out of > DE which > is produced by Dyna Grow. One of the distributors is Fred > Clarke of > Sunset Valley Orchids in California. I use it along with bark and > like the results. > Bev Tall > (Message-4) I believe what you're thinking of is diatomite, which is > crushed pieces of > calcined muds of freshwater diatoms. Essentially all > of the world's supply > comes from an Australian producer - Maidenwell - and it is imported as > diatomite by diatomiteusa.com on the east coast, and Dyna-Rok II by Dyna > Gro > on the west coast. > > Ray Barkalow ) _______________________________________________ the OrchidGuide Digest (OGD) [email protected] http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
