Browsing Archive: September, 2017

THE POLARISCOPE, THE FACETER’S FRIEND

Posted by Site Moderator Webmaster on Saturday, September 23, 2017, In : Faceting 

Duncan Miller

A polariscope consists essentially of two polaroid filters, or a source of plane polarised light and one polaroid filter. The source of polarised light can be a white computer screen or even the sky, viewed at 90 degrees to the Sun. For the filter, or analyser, you can use a sheet of polaroid, or a lens from a cheap pair of 3D movie spectacles.

Let’s start with a white computer flat screen. Even an older cell phone screen without a plastic cover produces plane polarised ligh...


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9th September, 2017. The Jan Coetzee Quartz Crystal Reunion

Posted by Site Moderator Webmaster on Saturday, September 23, 2017, In : My Collecting, My Collection 

About ten intrepid Jan Coetzee crystals made it to the reunion, with two of 50 kg-plus guys sending their apologies due to being overweight, along with a couple more whose owner couldn’t provide transport on the day. One rare and seldom seen fluorite (also from the same crystal pocket) came, and was much admired. Malcolm Jackson gave a short presentation about the mine and its location, along with photos taken by him and Jo of the Jan Coetzee mine dumps in recent years and the remains of th...


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