Make heavy cores heavy and a second idea as a portable fluid tank

So my first point is that the heavy core isn't realy heavy: it doesn't fall and just floats in the air. it would be realy cool if it fell like sand, but had a faster acceleration and if it could break blocks it fell on instead of the block breaking it (like how sand gets broken by a slab, but the heavy core would break the slab). it would also sink in bubble colloms

My second idea is a little more wild, but it does add a use for the heavy core after the player got a mace. if you look at the texture of the heavy core, you can see a 2x6 pixel black bar. that reminded me of a fill level indicator, so i got an idea: what if the heavy core could hold 64 or 16 buckets of a fluid, wich would even stay in the core if you picked it up. it would indicate how full it was using the black bar en it would be so usefull for filling a pond, building an overworld lava lake, building a powderd snow trap or getting milk en using it to raid an ocean monument.