The lime we are using is Singleton Birch NHL 5-Z, which is made in this county.  We were choosing between this and the French made St Astier Lime.  From what we have learned the St Astier lime has a greater compressive strength than the Singleton Birch and has a faster set.  Roughly speaking the St Astier NHL3.5 is comparable to the Singleton Birch NHL5.  This is because it is harder in this country to made a true NHL5.  On the other hand, the Singleton Birch bulks up better, and produces a fatter, creamer mix.  This makes is better suited to mortars.


Castle lime, which we will be using in the limecrete slab, comes from a similar region in France to St Astier lime and is better suited to things like limecrete slabs, where the greater thickness benefits from a lime with a faster set.