FMF - Friends of Minerals Forum, discussion and message board

[trtlman]

I have a bunch of magnetite, in fact I got it identified here, thank you all for the help with that. I was wondering if its possible for magnetite to not be ferrous? I have two stones that look just like my magnetite stones but one doesn't attract a magnet while the other has barely any attraction, and I am using a very good magnet. I wish I could post a pic but I am without a computer for a few months as I have mentioned in another posting.

Also I am wondering what are some common other minerals that can appear with magnetite? One stone appears to have quartz with and some others have other bits of stone or mineral mixed in. In fact very few seem to be without other minerals present.

[gemlover]

Magnetite can be confused with: ilmenite, chromite and franklinite.

Magnetite is found with: almandine, talc, chlorite, andradite, calcite, quartz, Baryte, fluorite, hedenbergite depending on the type of petrologic environment in which it was formed.

John

[trtlman]

Thanks, I'm going to have to look up those other minerals and as for my magnetite its from Idaho, I don't know where exactly where in Idaho.

[Luiz Menezes]

Magnetite can alter into hematite (at the rock where it was formed, during millions of years, not at anytbody's collection), Fe2+ oxidates into Fe3+ and it loses the magnetic properties and becomes a form of hematite (the so called "martite"), keeping the original shape of the magnetite.

[Nick Zakzuk]

Hi Daniel,

When you have a black, heavy and non-magnetic material it is always good to check it thoroughly. Iron can appear in nature without it being magnetic but a lot of times when it's heated it regains its magnetic attraction. I suggest you pulverize it, heat it and then try the magnet.

If you're interested, I can give you access to a digital copy of a prospecting guide which has simple chemical tests for identifying minerals (about 60 elements). Just PM me.

Keep in mind that nature is extremely diverse but I've found magnetite here right next to a gold vein. I've also read that there are dposits which include magnetite and have tantalum. Tantalite may be what you have in your hand. It's non-magnetic and very heavy. It's also worth $100/lb! The prospecting guide I mentioned has a test for it as well.

Best of luck!