On Mon, 13 Oct 1997 09:14:18 -0400 (EDT), JABandMcB@aol.com wrote: >Hi Folks, > >Sorry to take so long to......... >I finally received the information from the Association for Gravestone >Studies, both a Primer on Graveyard Preservation > and advise directed at my specific problem, lichen and moss. > >To summarize: > >Start the cleaning .......... mix 1 >cup of HTH (a product name for calcium hypochlorite - the same stuff used in >swimming pools-it is a biocide) into a gallon of hot water to get the >granular HTH into solution.................. following the application of HTH solution. This stuff >smells like >bleach but it is not bleach! DO NOT USE BLEACH. DO NOT USE OTHER COMMON >CLEANERS. > THIS POSTING IS WRONG!!!!!!!!!!!!!!! calcium hypochlorite is not a biocide it is a powerful OXIDIZER. It kills swimming pool algae by "burning" it up. calcium hypochlorite mixed with water is Bleach, Just look on a bleach bottle. Household bleach is about 3 to 4 percent available chlorine, HTH is about 65 percent available chlorine. The formula of 1cup per gal. is equal to 8 oz to 128 oz. 8 divided by 128 = 6%, as the HTH is about 65% 6% times 65% = 3.9% In other words the formula is equal to bleach right out of the bottle. For the cautionary statements and warnings read a bleach bottle. As for grave stones maybe it's safe maybe it's not. But it WILL cause rapid oxidation of any materials that it contacts which are susceptible to oxidation. Including any iron fittings or decorations that may be present on the markers. Dan ==== PENNA-DUTCH Mailing List ==== Abbreviations---PD=Pennsylvania Dutch, PMH=Pennsylvania Mennonite Heritage magazine, MFH=Mennonite family History magazine, MRJ=Mennonite Research Journal, LMHS=Lancaster Mennonite Hist. Society. This and more list info at: http://members.aol.com/PennaDutch/pennadutch.html