I am no expert on this topic, but I feel this is similar to how ferrofluid forms "spikes" when placed near a magnet. Are they related?
But yes, Maybe I'm interpreting the video wrongly. Yet, to me it looks like the bulky part of the sample is being repelled by both poles of the magnet as it stands upright with the pointy end at the bottom each time. IMHO if this was due to attraction, the pointy end would be at the top.