Baldy Beacon rocks

On a recent trip to Baldy Beacon, Mountain Pine Ridge, I picked up these square/rectangular rocks.

Metallic mineral

It was quite exciting to spot this rock over the weekend on a family getaway. Thinking at first it was molten iron, I picked it up to see it was a rock. Someone sugested it could be either pyrite or magnetite. Or does anyone reading this know which metallic minerals can be found in Belize?