In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
I work as a building plumber for The City and County of San Francisco. The Stationary (boiler) Engineers I answer to often have me impersonate a steamfitter (usually to replace valves) and work on steam and hydronic heating lines in the building. For copper tube lines I braze ("silver/hard solder") the connections, but for the threaded connections I use the same Blue Magic or Rectorseal brand pipe dope and teflon tape that I use for potable water. Before manning the plumbing/piping shop at this bulding by myself, I was part of a crew of plumbers and genuine steamfitters who shared a shop (though we had seperate locker rooms as well as seperate supervisors who each answered to the same stationary engineer). When I called my vendor (who have the word steam in their name) to ask what I should use for high heat threaded connections they just say to use Blue Magic, but I remember that the steamfitters used a different kind of pipe dope that was grey in color, so I suspect that their must be pipe dope and tape that is better for steam and hydronic heating lines. I haven't found any answers in "Modern Hydronic Heating" or in Dan's books so I'm asking you. Please tell me what to use for threaded heating piping and components.