I made a couple very interesting finds here in S.E. Michigan. After researching my local area and wondering if I was just wasting time looking for Gold, I decided to check all the rocks in my own back yard. A neighboring business decided to build an addition to their building and had dug down almost 20 ft to dig a basement/addition. I allowed them to put all their dirt/rocks in my back yard as my yard was like a sinkhole from water runoff from everyone else's property. I have found several artifacts and a few rocks with Gold streaks. Also, my house is a Victorian built in 1888. It has a Stone foundation and I decided to check out all the rocks in the basement. One rock, about the size of a baked potato, was under a basement window sill and was easily picked out of the wall. (No, my house won't fall down now..

but it has Alot of Gold flakes concentrated on the surface in a vein type pattern with a 2 inch square size of concentrated Gold flakes. Its the only rock like it that I've found so far but I'm thinking these foundation rocks are from the area locally since the house is so old that when they built it, they wouldn't have carted foundation rocks from very far away.
Does anyone have an explanation or knowledge of how foundations were built so long ago? Did the builders mostly use the rocks from the basements they dug to build the foundations? Since it was Horse and Buggy days, I don't think they dragged rocks from very far to build these homes. Thanks for any input, I'm very curious about my recent finds...