I have always coveted a chunk of tungsten, but be aware that there's some implication that it's a carcinogen[1] though that's a bit unclear if it's actually other metals it is alloyed with (in which case the purer the cube...)
I suspect handling a tungsten cube delivers very little tungsten into your bloodstream, even if you lick your fingers afterwards. I'd imagine munitions or metalshop grinding/polishing generates many orders of magnitude more microscopic metal dust.
You could always coat it in polyurethane - a clear coat shouldn't diminish the impressiveness of the density.
> "In September of 1994, a French soldier drank wine from a rifle barrel. Fifteen minutes later, he started having seizures. He was rushed to the hospital and treated for 'acute tungsten intoxication'—the first known case in medical history. He reportedly made a full recovery, although concentrations of tungsten were present in all his body tissues for weeks."
Grinding tungsten is also something that is done in TIG welding: it becomes periodically necessary to grind a new point on a tungsten electrode. (How often this is done varies according to how steady a person's hand is.) I think of this story about the French soldier as a good reminder not to lick my workbench next to the grinder.
I would worry about the thorium in thoriated TIG electrodes more than tungstens toxicity.
Thankfully it is in the process of being phased out as an additive, too bad that it is a very good one, if you ignore the radioactivity.
I've never tried (or wanted to try) thoriated tungsten. I've always just used lanthanated, and it seems to do the job. Last I checked, thoriated was cheaper, so maybe that's a draw for some people. I don't know if thoriated is better in any situations; I was under the impression than lanthanated works just as well.
1: https://academic.oup.com/milmed/article/172/9/1002/4283401?l...