Tuberale in the vernacular of metal detectorists "black sand" is the term used to (specifically) describe/define magnetite and hematite deposits found in soils, especially magnetite. Firstly, Oregon has a over-preponderance of it as regards to metal detector operational behavior when detecting in it. One can see the streaks of it in both wet and dry sand on Oregon beaches, and I have written scrolls about it. I have hauled buckets of it back home to Sweet Home where I live - and have also gleaned it from the Oregon coast beach sand to examine the %'s of it found in that soil. As we all should know magnetite is by and large our biggest problem here. I think you may be reading in a bit too much petrology from my black sand statement Tuberale, so that may well be the misunderstanding.
Here is a decent article about black sand: I think you will enjoy it;
www.nevada-outback-gems.com/Reference_pages/black_sands.htm
That southern Oregon area is quite interesting, I lived in Coos Bay for awhile, and nearly got eaten by a cougar one day. It is still fairly wild at best in some places, and yes I know what you say about older rocks in the area. But that is another story.
Oregon's biggest nightmare when trying to detect here is magnetite precipitation deposits, and they well know that at white's Electronics right down the street too. I stop in there now and then and have been involved in a business adventure with one of their quality control personnel employees in the past. I wasn't born in Lebanon, but my adult children were. When Teknetics got it's start in Lebanon I had a conversation with George Payne about the magnetite problem here too. He too is well aware of it. Everybody who is part of this game and who has been at for awhile, including those at one of the world's largest metal detecting businesses, of which I was privileged to have been involved in the development of and the engineering of some of it's products via a private designing/manufacturing firm - are aware of the magnetite problem too. I cannot go any further with the manufacturers discussion though, because it is tied in with The Department of Defense and is a case involving Top Military Secrets. But yes, there are areas inland that have sufficient problems with black sand or other mineral deposits/rocks too. In Washington State there is an area on the central coastline where my Surfmaster wouldn't work at all, and of course neither would any multi or single frequency detector. A magetometer might be the way to go. I may care to explore that area some more too, if I can find the right hand-held machine.
My main interest as regards to metal detectors is to be able to do better than I currently do to search on Oregon, California, and Washington State coastal beaches search for jewelry and old coins. I want to keep it light, easily portable.
Thanks for the input Tuberale.
Brian, do you think that the Gold Quest SS is very practical for my needs or would it be too tedious and slow for one who prefers to go at a roadrunner's pace, like myself? And the same question goes for the Deepster. I'm not looking forward to being caught in a peat bog of heavy and cumbersome contraptions - if I can at all avoid it.
Thanks guys for the input, I'll do some thinking about your posts.
LL