Assuming that's about 5x5', and going by the price of the first tungsten cube found on Google, this would be worth about 15 million dollars. Decent prize of you could move 150,000lb.
This could possibly be the worst possible prize. Raw tungsten isn’t actually that expensive. What’s expensive is working with it as it melts 3,410c (6,170f) isn’t very malleable and is heavy like really really heavy to move this block you will probably need larger equipment than standard industrial moving equipment, bigger trucks and loaders also you’ll need to get the city's permission to haul it on the roads , that alone is probably going to cost more than the cube is worth you will then have to pay a monthly storage fee until someone wants to buy it. Shouldn’t be that long right? It’s a valuable metal… well good luck finding a company that works with tungsten outside of china, and you absolutely can not ship it. But let’s assume you find someone who wants it(at a considerable discount) well now you have to higher the specialized movers again.
EDIT:
Actually I just did the math and plugged in all the known values I could find and assuming you could sell it within the first year you could probably make $700,000, so it would still be well worth it. But a lot of trouble.
I really wanted to use Tungsten as the base ballast for a custom narrowboat, for better headroom. Other than the cost you also have the problem of tungsten’s melting point being so high you can’t pour it into a boat hull without melting through.
Just to be a troublemaker, everyone is assuming this a solid cube, but what if it was something like 1/4 inch tungsten plates and hollow in the middle?
I just looked it up; assuming that thing's about 5ft³, that thing is worth like $54,000. Granted, you're going to need somebody to come haul it off, but at 10.66k per cubic foot, I'd say it's not a bad prize.