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columbite with matrix or not?

Posted by Pekka Ruoho  
avatar columbite with matrix or not?
August 01, 2012 02:51PM
I am trying to clean a small piece (crystals) of columbite from Kaatiala in Finland.

..and I would like to get second opinion. Should I try to clean away all feldspar and small parts of columbite crystals on the top of it, or
should I leave the matrix. I am pretty sure that there are more well terminated crystals inside of feldspar.
avatar Re: columbite with matrix or not?
August 01, 2012 03:07PM
Its not a bad specimen as it is. I would use the high pressure water from one of the new spot cleaning guns that are in common use by dry cleaners to see what I could clean off. Then I would probably use a small pneumatic hammer to try and remove a little of the feldspar to see if any significant other columbites? were worth exposing. Then I would put it in iron out to remove the minor "iron" staining.

Rock Currier
Crystals not pistols.
avatar Re: columbite with matrix or not?
August 01, 2012 04:40PM
Since it is already so good, I would keep it as it is.
Is it a recent find?

Re: columbite with matrix or not?
August 01, 2012 04:45PM
Hi Pekka
If I where you, I where very contented for the specimen as it is, because the columbites are very fragile and even small
vibrations, can do that you, got some of the crystals broken. Do not that problems to you!!
Try only oxyal acid for the rust, or any other thing good for removing the same.

Terv. / Ulf thumbs up
avatar Re: columbite with matrix or not?
August 01, 2012 05:58PM
Thanks all!
I just removed broken pieces of feldspar and found even in top part one terminated crystal. Here some new pics.

.. now it is taking bath. I have broken many big rocks in Kaatiala and have many "singel" crystals. This time I took with me a smaller rock with broken crystal on surface. When I hammered it at home I found many small crystals and this group, which I like for its estetical look.
rgds PekkaR

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