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Hamilton possible polydymite

Posted by Timothy Greenland  
Timothy Greenland February 25, 2012 07:02PM
Are there any Hamilton fans that could help me with this specimen? I got it by exchange back in 1964 from WB Sanborn of San Francisco with the label "Millerite in Calcote, Hamilton, Hancock Co. Illinois, U.S.A.". I was always intrigued by the curvy needles of the included material, as all the millerite I knew was basically straight - with occasional deviation... On looking at the Mindat page for Hamilton, I saw the pictures of polydymite in calcite which look very like my piece. Can anyone give me an informed opinion???

Ist photo: Overall view with centimeter scale. the largest calcite crystal (essentially two nail-head terminations without prism) is a bit over 2 cms across. The colour is not quite right - the background should be pure white.

2nd photo - close-up of the included needles FOV ca 5mm. Stack of 5 through-focus views. The double refraction of the calcite causes some of the deeper hairs to form double images.

Any comments will be most welcome


open | download - Ham1a.jpg (78.5 KB)
open | download - pydStacka.jpg (55.2 KB)
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