I bought it last week from J&Ls.
Works great once cured.
I did have to use Aquaweld to hold the rocks in place before applying the Mortar.
Gel super glue should work too.
I like the Aquaweld because it hardened very quickly, no mess and reusable. Although I wouldn't recommend it for smooth surfaces. The more uneven the surface the better it bonds, especially with holes.
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