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LocalitiesLoudville Lead Mines (Manhan Lead-Silver Mine; Southampton Lead Mine; Northampton Lead Mine), Easthampton, Hampshire County, Massachusetts, USA

19th Mar 2012 00:16 UTCSteve Stuart Expert

I've been taking another look at material I collected at Loudville in August 2001 and found these interesting micros (2mm FOV):

Any ideas about what they might be. Barite comes to mind as my first guess.

Thanks,

Steve

19th Mar 2012 00:55 UTCDavid Bernstein Expert

Steve, reminds me of Cerussite.

19th Mar 2012 01:51 UTCSteve Stuart Expert

Seem to be odd habits for cerussite, but you might be right.

19th Mar 2012 01:57 UTCPeter Cristofono

Hi Steve,

Barite would be my guess. One thing you could check is fluorescence. Cerussite from Manhan has pretty good yellowish fluorescence under LW. Barite from Manhan does not fluoresce.

Peter

19th Mar 2012 02:50 UTCSteve Stuart Expert

No fluorescence on either specimen. My cerussites from Loudville do fluoresce yellow to yellow-orange under LW. The white rectangles in the first image look very much like Peter's barite images in Mindat. Peter, if you are comfortable with the zoned mineral in the second image being barite, I'll post the image to Mindat. Or, we can wait to see if other opinions get posted.

Regards,

Steve

20th Mar 2012 02:20 UTCSteve Stuart Expert

I have another Loudville puzzle. Here is an image of what looks like acanthite:

There is another image in the Mindat gallery of a Loudville acanthite with some caveats about visual ID only. Also, acanthite is not listed as found at the Loudville Mines. Any later update or mineral list that would allow a sourced addition of acanthite to the Mindat database?

Thanks!

Steve Stuart

20th Mar 2012 21:32 UTCPeter Cristofono

Hi Steve,

I don't believe I've seen a published report of acanthite at Loudville, but what appears to be acanthite is often noticed by collectors as a post-mine (and even post-collecting) occurrence.

Check out this old Mindat thread for more info:

http://www.mindat.org/forum.php?read,11,42147,42377

Regarding your barite: Your second image is unusual, but I don't know what else it could be.

21st Mar 2012 03:51 UTCPatrick Haynes (2) Expert

The Manhan River Mine has lots of nice, blocky, white, micro baryte, just as in your images. The acanthite I have not seen.

24th Mar 2012 17:07 UTCUwe Kolitsch Manager

The first two photos clearly show baryte.

24th Mar 2012 21:06 UTCJim Robison

Hi

Late to the party, and not objecting to barite, but responding to the comment about the funny appearance of the second image. I think there is a hidden optical illusion in this pic. When you look at an image without any well defined horizontal and vertical points of reference, the eye/brain connection sometimes 'assumes' that the image is flat and parallel to the viewing screen. If that were true, then the crystal appears to be a rhombohedron. If you recognise that the cute little zoned crystal is in fact being viewed at an angle from the upper right side and end view, it is probably sloping into and down to the left of the image. With that in mind, it is clear that this is not a rhombohedron but rather a crystal with 90 degree corners. If you live in a two-dimensional world like I do (can't see with my right eye) then this effect is all the more pronounced. Artists using this illusory effect can create some marvelously confusing drawings.

25th Mar 2012 15:46 UTCSteve Stuart Expert

Hi, Jim!

I looked at the second barite again under the microscope and could not find any orientation that resulted visually in right angles for the corners of the zoned tablet. So, my original photo was very close to an orientation normal to the plane of the crystal. The angles are not 90 degrees. I still go with barite.

Regards,

Steve

25th Mar 2012 21:02 UTCJim Robison

Steve

Thanks for looking at crystal orientation again. Just goes to show how a perception can be misleading. Nice zoned crystal in any event. I envy those who can use a stereo microscope to see the third dimension. For me its a flat world, with shadows helpful to show depth if they are present. My second lens on the scope is a nice brace for my forehead if I'm not careful. Not good for much else except to hold my small scope camera.

25th Mar 2012 21:50 UTCSteve Stuart Expert

I attach my camera to the right ocular after I find the scene I want to image. See below:

Steve

2nd May 2014 16:37 UTCrocks

I just found several didn't rocks or minerals not sure what the r or if that could be worth something. I have a few small one and one medium size one.

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