Home made mortar

[Cornbelt]

 Any of you guys know what the mixture of old mortar used to be?
  I'm building a temporary furnace for boiling syrup this year and want to make it more permanent by next year. Also don't want to use bag mortar in case I have to tear it down sometime in the future.
 
 For the temporary, I'm just using sand, ashes and lime.  Some sources say gypsum or plaster.  Anyone have an idea?

[keith44]

when they blocked my foundation they mixed lime, sand, and portland cement.  Why they added lime to the cement I cannot say, but other than water that is the mix they used here

[Cornbelt]

  On the old mortars where they didn't use portland cement, or at least used very little, it never got hard enough to crack without getting soft enough to heal the cracks when it got damp again. With whatever else, its a major ingredient.
 Did they use barn lime or slacked lime?
  I got last year's project all torn down, but eventually I'll be building a more permanent set-up, and I'd like to keep the older recipie  -if I can find one.

[keith44]

just a theory here, based on your needs (since all I am finding uses cement) have you thought about the old brick mixtures??  Clay, sand, and hydrated lime.  Without firing, it should be self healing during wet times, but would be easily fractured due to excessive drying.

[Cornbelt]

 If I happen onto the right destruction site, I'll be able to shovel it up, and not worry too much what's in it. And I know where one is about to get demolished. Maybe I can time it right.