Could be many things, but certainly literature like stacked...

Could be many things, but certainly literature like stacked lodes, open at depth could have something to do with it.
I remember when I held BGL from 30c and sold around $1.20,
The resource kept creeping up ,when I SOLD OUT I believe it was about 2.7 million ounces in resource and now it's about 3.5 million ounces resource. As we can see it's a long hard road to become a miner and they had a pretty decent head start with all those old underground tunnels.
If we are fortunate enough to strike a decent resource of a million or more ounces of shallow high grade gold, those sort of ounces could be worth $1000.00 an ounce in a major prolonged precious metals boom.
GLTA