Hi Reiner, I actually remember taking the photograph (166448) of this specimen, as at the time it was somewhat problematic, as you suggest. Indeed, there were minute spherical aggregates of the mineral present, but this is not seen in the photograph due to the inadequate equipment I was using at the time, compounded with what looks like a bad scan of the original film and even worse post-processing. In Łukasz's image (776653) you can see in the lower right quadrant what looks like to be the terminations of the olekminskite, in a crystalline barytocalcite matrix. Łukasz will need to confirm, of course.
Moderators - would be OK to delete image 166448, due to poor quality.