They look a bit fragile, and your container looks a bit deep. You might want to try selecting the very best large crystal and removing it from the jar with extreme care. This will be your seed crystal. Then add just enough lukewarm heptane to redissolve the crystals that remain in the jar. Suspend the large crystal on a fine thread so that it is immersed in the - now cooling - solution. Hang it off a pencil or coffee stirrer or similar, then cover the top of the jar with plastic film to slow the evaporation of the solvent. Keep in a place away from light and vibration, at a steady temperature. Some weeks later you might find you have a lovely, large crystal cluster hanging on your thread.
Minimizing the presence of dust and other nucleation points such as scratches on the glass surface will assist in growing larger crystals on a seed crystal.
This wasn't really what you asked but I hope you find the indirect answer helpful nonetheless!
“There is a way of manipulating matter and energy so as to produce what modern scientists call 'a field of force'. The field acts on the observer and puts him in a privileged position vis-à-vis the universe. From this position he has access to the realities which are ordinarily hidden from us by time and space, matter and energy. This is what we call the Great Work."
― Jacques Bergier, quoting Fulcanelli