Electricity from small rock

[hemancro]

that's a cool video, i watch it and done some experiments myself. failed tho
i live now in thailand, that black rock is common here.
i found some brown one that give me output 0.7V-0.8V and 0.001 mA
and some other black 0.9 to over 1 V and 0.003 mA
but then again i need aluminum foil. i cant work with scarp metal.
it don't cover all surface and my voltage and amps go down quick.
now i'm sure that it has to do something with minerals in rocks.

[hemancro]

here is video of my concrete battery.
http://www.youtube.com/watch?v=rLgHWYGydng

it charge 35200uf 35V capacitor and light LED with joule thief.
please note that this battery is more than 6 months old and still produce electricity 0.9 V and 1 mA. i have made those 20.5.2010.
power dropped ofc in first 2 months and after that stay at 0.9V and 1mA

[hemancro]

i want to make update on progress.
at first i needed 1 day +- few hours to charge 25uf capacitor with 1 rock to 100mV.
now i need 5 min to charge 100uf to 250mV.
that's huge improvement.

now i want to give you some numbers.
i have 10 rocks. every rock give me 300+mV and 10 rocks give 0.001mA
10000 rocks can give 1mA at 300+mV
150.000 small rocks can give 5mA 0.900mV.
i know its little power , but i think its constant.

i still not sure what give electricity. minerals in rocks, some form of radiation or what ever, but its there.
tomorrow i'l post 1 more video of charging 1200uf capacitor, and after that i hope il be able to light LED.

if someone know more, please share.