preparing found rocks for the tank

well I decided I wanted to add a bit more interesting terrain to my tank and remembered I had a bucket of fist sized rocks from a lake up in far northern wisconsin. I figure anything that might have dissolved out of the rocks would have likely done so already since they've probably been there since the last ice age. the lake is pristine with no pollution worth mentioning (you can drink the water out of it, its so clean) so all I should need to do to the rocks is wash them with some dish soap and rinse well before putting them in yes?

their some form of quartz with limestone I think (bright white with crystals etc..) one looks like some form of rose quartz

 

a tire brush and warm water is all I have ever done

 

I'm a newbie and soaking everything I can from this great forum ... one thing I've learned from different post here is that any kind of soap is harmful to the aquarium/fish. I hope others chime in on how to properly prepare your rocks. From the way you describe the water, I agree with cichlidman.

 

You won't want to use soap on them. What I did to clean my rocks was first scrub them really good, then soak them in warm water for about a week

 

Just clean them with warm water. Drop them in some white vinegar if they start to bubble don't use them. What ever you do never boil rocks they can explode ( well violently crack ).

 

Are you sure there is no iron or other metal in them?

 

Iron is red. My two cents.

 

No dish soap!