Base Rock to Live Rock

[Ron99]

What is the general consensus on how long it takes a piece of base rock to have sufficient bacterial growth etc. to be equivalent to live rock after being added to an existing tank with other live rock?

I ask because I am building a pico tank and want to put some small pieces of base rock into my 10 gallon to "cook" so they can end up being live rock in the pico.

Thanks.