Why do they put lime on dead bodies, such as in mass graves? Does it accelerate or hinder decomposition? What exactly happens?
As a note; This question is out of curiosity, but don’t have to come to my New Years party if you don’t want to.
According to this site:
lime masks odors
The question probably stems fom a confusion between Garden or Hydrated Lime and Quicklime or Caustic Lime.
Quicklime is very caustic, and burns human skin on contact. It has been used in mass graves for hundreds of years to help prevent the spread of disease and mask odours. It does in part this by sterilising and dehyrdating the exposed body surfaces and making the grave unattractive to insects and scavengers. I imagine as a side effect it would help preserve the copses to some degree as well.
I suspect that criminals putting lime in graves have made two mistakes. First confusing quicklime with garden lime, which would do almost nothing to a corpse, and second assuming from historical records and documentaries that quicklime was meant to speed decomposition rather than simply preventing disease spread and keeping the air fresh.
I use garden lime in my compost bin to speed decay, but for reasons that probably wouldn’t have any effect on a human corpse.
Okay, so what would you use to get rid of a corpse? It has to be something fairly cheap and easily available or I can’t … oops!
Best way to get rid of a corpse: saw it up in little pieces, presumably in the bathroom, and then put them in a suitcase and dump them in the East River. Possibly bury a piece or two under the roses at the end of the flower garden.
Oh, and IMPORTANT: Be sure that no one in a cast with a telephoto lense is watching you from accross the courtyard.
Invite all your friends for Christmas dinner-----
Oh, jeez. I got GE on the west side with PCB’s, and now I got Dex and Hitchcock on the east side with lord-knows who?
Can’t an island get a break around here?
Hey, Manny, I got it even if most of the others didn’t.
Although many people have heard of the act sprinkling of lime over a corpse, few people ever remember the second, and ultimately more important act, the application of salt, and the dousing of tequila.
Heh.
Hey, barkeep! Give me a maguerita, and make it stiff!
And if you’re going to dovetail Faulkner and Hitchcock, it’s best to sprinkle lime throughout the yard if you are intent on keeping the body of a loved one in the home.
We’ve had skeletons recovered here (Newfoundland) that are estimated at well over 300 years old (could be over 1000 - I forget the exact number and my notes are elsewhere). The skeletons are kept in good shape by lime. It counteracts NF’s naturally acidic soil profile; I guess the folks that used large limestone slabs as covers for graves knew of the effect.
Obviously, using limestone would be a great mistake if you want to conceal a murder. I unfortunately don’t have any information on how using a lime product would speed decomposition. 
FD.
<-----reaching for flash gun and spare old-style flashbulbs…wahoo, that insane bastard will NEVER fit me out of that windoooooooooooooooooooooooooooooooooooo.
Cartooniverse
Apologies for resurrecting an old thread, but it was recently referenced here.
Actually, the “lime” sold to gardeners is usually mainly limestone, which is calcium carbonate (CaCO[sub]3[/sub]). It usually contains magnesium carbonate as well.
“Quicklime” is produced by heating (calcining) limestone, and consists of calcium oxide (CaO) and magnesium oxide (MgO).
“Hydrated lime” is produced by adding sufficient water to convert the oxides in quicklime to hydroxides. Hydrated lime is thus primarily Ca(OH)[sub]2[/sub] and Mg(OH)[sub]2[/sub].
You can get more info here:
http://www.lime.org/faqs.html
http://www.sigmaminerals.com/aboutlime.htm
(I just did a project involving the use of lime.)
How many bodies?
Picky, picky picky.
Perhaps I should have said "a confusion between Garden or Hydrated Limes and Quicklime/Caustic Lime.
Happy now? 
[sub]Wanders offf muttering under his breath. [/sub]
Word trivia: “Sarcophagus” (a stone coffin), means “flesh-eating,” (derived from Greek sark- “flesh” + phagein “to eat”), based on the early belief that a certain kind of limestone would consume flesh if a body was placed in a coffin made of it. I’m not certain that this was true, however.
If you reeeealy want to get rid of a corpse, you run it through a limb shredder and mulch yer garden. Don’t forget to roto-till afterwards. (And maybe sprinkle a litte lime…salt…NO! Won’t do it!)
Hey now, don’t get your undies in a twist. My nitpick mainly arose from the difficulty I had in getting the lime for my project.
I needed Ca(OH)[sub]2[/sub] for my grad school research project. So I head down to S-Mart[sup]TM[/sup] because I saw the big bags labeled “LIME.” (I say to myself, surely these bags actually contain hydrated lime because there’s no way they’re selling caustic quicklime to Joe Gardener. Was pissed to find out that the bags did indeed say “LIME” in huge letters, with the note that the contents were actually crushed limestone. Crap.
Off to Home Depot. They must sell hydrated lime there. People use it for mortar. Find some. No indication as to the chemical composition. Write down the name of the manufacturer and the town they’re in. No such company exists. But there is one other lime manufacturer in that town. Call them. It’s the company I’m looking for. They changed their name. Very nice guy at the company faxes me an MSDS. Turns out his product is “dolomitic hydrated lime” which is 75% Ca(OH)[sub]2[/sub] and 25% Mg(OH)[sub]2[/sub]. What I want is “high-calcium hydrated lime.” Is this produced at his operation? No. Crap.
Consider just buying lab grade Ca(OH)[sub]2[/sub] from Fisher Chemical. For the 100 lb I need, this will cost over $1000. No go.
Hit the web. Nearest manufacturer of high-calcium hydrated lime is in Canada. Track down a distributer in Cambridge, Mass. Only 2 hours away! Call them. They actually ship to another distributer in Fall River, Mass. Only 30 min. away. Alright! Go there and buy it. Total price $8.50.
Only took me 3 weeks. Sheesh. Never realized “lime” was such a generic term, but now I know more about lime than I ever wanted to. And filled with a burning desire to share this with fellow dopers.
So does “lime” accelerate or hinder decomposition of dead bodies? Heck if I know…