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Identifying Minerals Found In Gold Producing Areas


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Doing some testing I believe the black mineral inclusion in quartz, luster(y) polished, similar hardness to the black nodules, brown streak, not attracted to a magnet is hematite.
 

The other black nodules are strongly attracted to a magnet, have a black streak test, are dense and hard not scratched by quartz I am guessing are ironstone nodules? What say ye am I on the right track??

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Think you got it. Probably magnetite for the ones attracted to magnets.

If the black mineral in quartz is actually brown streak and not sorta rusty/reddish brown then it might be goethite. It tends to be blacker than hematite. Also, it appears it this mineral is weathering to limonite (yellowish stuff at the outer layer of quartz) and that generally means more geothite than hematite. But, could be either (or varying degrees of both in some cases) and comparing the streaks of a known piece of hematite and goethite to that unknown mineral should tell the difference. 

Cutting either of those on a saw like it looks like you've done will make a nice mess, coloring the cutting oil the streak color of the mineral. 

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Thanks Jason for the reply, out detecting I tend to just lump them all into a generic class as hot rocks and ironstone, magnetite and other minerals with iron or iron looking qualities but doing so is not helping me use the information they give as it relates to finding gold. 
 

additionally a youngster maybe 8 or 10 yrs old the son of one of my doctors is crazy for geology I discovered when one time giving my Doc a gold basin meteorite on a day it just happened to be his sons birthday and he was thrilled to have this for his son… the boy was thrilled to get it and his dad was a hero bringing it home. I’ve since sent him a gold nugget and now I look for interesting rocks to send the kid through his dad but figure I should be able to at least identify the minerals if I can? So that’s the most important thing about this question, thank you.

The one in quartz is a light reddish brown streak and I visually selected it I don’t think the 6000 hit on it, the others definite dark streak I’d call black that the 6000 can’t ignore and very strong attraction to a magnet but not magnetic itself are the properties I observed. 
anyway thanks Jason very much!

 

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