On Fri, 02 Aug 2013 13:40:50 -0700, wrote:

...snip....

Thanks for the post, but it doesn't really answer my questions.

Are you suggesting a lime mortar with no cement? That contradicts the
info at sacredplaces.org, which recommends a small amount of cement in
the mixture. And the wikipedia article doesn't say what specifications
I should require from a mason.

I know about the specifications for types M, S, N, O, and K mortar. My
question was, is the correct mortar for historic brick one of those
types, or something totally different?

Do you have experience repointing historic bricks?

Jimmy

Contact local, or nearby City's Historical Society. Large cities have some
very skilled, knowledgeable people who will help with your question. Also,
I've had no trouble reaching people at the Smithsonian in Washington, DC.
who either told me how to do something myself, had me send items to them
for repair, or provided a LONG list of recommended/approved 'repairers'