gold diamonds and natural geological wealth underwater

[popolarbear]

I am curious to understand or hear about what other members know of local gem and mineral hunting underwater. i myself am mainly a fish freak, and have little interest in geological or mineral studies. but it is interesting even so. i have had some other more serious in the subject tell me stories of finding this stuff. actually i have now herd this from several different people so i think this is going on in Minnesota. in fact i have seen gold samples that were taken and they tested true. diamonds also in certain areas and silver of course.
my interest being that these people would only hint at what the search entails, but i think it should be fairly straight forward. for instance much of Minnesota was at one time volcano's. the feet of which are were in Africa the richest deposits of diamonds in the world are found. in Minnesota this roughly coresponds to the areas that have heavy granite formations, then in these areas sometime you find a kaolinic clay that can contain diamonds. interestingly rumor has it that there are some areas were this clay has been mined ...but it has no use except for the extraction of diamonds... anyways early settlers came to Minnesota to find gold and silver using very primitive and simple equipment, they did find some limited amounts. today most of Minnesota is private or probably state owned as far as minereal rights go, but for someone just to stumble upon say afew ounces of gold or silver I doubt if anyone would notice if it was rescued from waste.....

my question is does anyone know much about the underwater search and find of such things? i am curious if certain types of formations or outcrops tend to yield such finds. etc.(private or public discusion fine)...also curious how many pounds of silver or gold most typical small surface viens produced in our area durring the early years of gold mining in minnesota?

[arcFlash]

That makes a lot of sense. The diamond in Alaska are at the bottom of lakes. The lakes sit on top of kimberlite which is what Africa diamonds are in.

[DiverQueen]

Parts of Lake Superior are well known for their Lake Superior Agates.  (Agate Beach, MN, Copper Harbor, MI)  The Mille Lacs Lake area through Aitkin County, agates are frequently found in farm fields and all over. 

[popolarbear]

Yes Yes Yes. that is exactly what I'm talking about. i think certain structures will yield themselves to this type of formation. it might be that in the right area, these things have accumulated in piles of them.

[popolarbear]

what color are the agates from mille Lacs?  apparently agates can come in other non-traditional colors like yellow, or green, or even purple.(all of which i have seen) comming from permian deposits, of which we have some.
this is getting off of my original topic of purely understanding how natural minerals are moved or processed by the water, but many areas of minnesota have some limited fossils that are exposed by the waters natural movement. western side of state has cretaceous shark teeth(small ones) and some very rare occurances of dinosaur material. but most of the state is much older seas. most interesting are trilobytes and crinoids both of which i dont know of any good locations that they come up. one spot in the mississippi by ford park has on rare occasions produce a varriety that runs almost 4inches long, but are never found compleate. I also saw another type that was larger almost 8inches in anther location. but poor preservation.

[DetectorGuy]

The crinoid fossils near the Ford dam and hidden falls area are fairly easy to find.
  As far as agates go... The ones in Mille Lacs were places there when the glaciers came by. these would be just dumb luck to find. If you want to find Agates with out luck you need to go to the source, lava flows. lava pushed these agates up from deep in the earth and later picked up by the glaciers and dropped in various spots (glacial till). Along the North shore there are lava flows still visible both above and below the surface. Agates are still embedded in these lava flows if you look hard.
  Thompsonite is found all along the North shore North of Two Harbors.
  There is a very rare rock only found near the Split Rock Lighthouse... and I can't remember the name of the stone. it is so rare that it is only found in two places on earth: near the Split Rock Light House, and somewhere in Europe. It is also found on the moon from the books I've read.
  Gold. There have been some findings of placer gold near the Red River Valley.

[arcFlash]

DetectorGuy, is the rock you speak of Anorthosite? There is a large dome of it that I've done some rock climbing on. it's very course. 3M made sandpaper with it.

[DetectorGuy]

Yep... I think thats right... My mom wrote a book on the Geology of Minnesota and I will ask her tonight. It is some crazy moon rock.

[popolarbear]

crinoid fossils Ive seen by ford dam were mostly fragments. best piece i ever found was a large root section of were the animal roots itself to the ocean floor. very rare find. i sent to a crinoid expert who claimed to later lose it. then i find from one of his friends that he sold it for a small fortune. he did send me some garbage fossil back.. which i gave to neighbor kids.as to crinoids there was a spot by hw394(Minneapolis) that yielded nearly complete specimens. not much left of that location.

as to moon rocks. many areas of lake bottom are like featureless sand boxes. if a rock was found on this sandy run.. it stands a chance of being of extraterrestrial origin. just like finding rocks in the tundra in spots they don't belong. meteor guys use this technique to go out and collect tons of otherwise impossible to find meteors. curious if any divers have systematically collected these out of our lakes.

[DetectorGuy]

I checked with my mom and it is Anorthosite. I guess the purest form of it on earth is on the west bank of the bay in Grand Marais. The area you were rock climbing was it Palisade Head or Shovel Point? As far as the 3M sandpaper, a couple years ago I dove a 3M dock crib from 1902 near shovel point where they mined corundum for grinding wheels. The cribs are still there and it is very very close (150') to the "cave of the winds dive site". To get to the site from shore you could park on the shoulder of Hwy 61 near the intersection of Hwy 1 just North of Tettegouche State Park. Just South of here is Shovel Point. It is not named because it looks like a shovel but because a barge carrying shovels sank there and the shovels are rumored to be all over the bottom. Here is a link to that dive trip: