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FACETIPS – A GEM CUTTER’S NOTEBOOK

by
Duncan Miller


The faceting articles published over the past few years in the Mineral Chatter have been compiled into a single 128 page document, available for download for those interested in saving all the articles together. To download the pdf file click here.

A 29,18 ct cuprite from Onganja, Namibia, cut by Duncan Miller and now in a private collection in Germany.


Browsing Archive: May, 2017

New Barite Occurrence at Rosh Pinah Mine – Namibia

Posted by Site Moderator Webmaster on Tuesday, May 23, 2017,

Transparent to whitish barite mineralization was found in an orogenic late phase leached fault zone. It seems that some of the barites are pseudomorphs replaced by snow white baritocalcite. This replacement supposedly took place at an even later phase when calcium-rich fluids migrated through the formation. This theory is supported by the occurrence of floater quartz crystals in a pocket where, on the one side, the quartz aggregates display the luster of ‘bergkristall’ and are coated on t...


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The History behind the Mike Lurie Collection

Posted by Site Moderator Webmaster on Tuesday, May 23, 2017,

The Lurie family lived in Bulawayo, Rhodesia/Zimbabwe, from 1951 to 1966. During this time Robert’s late father, Mike, worked as a manufacturer’s representative. His job took him by car all over Southern Rhodesia (Zimbabwe), Northern Rhodesia (Zambia) and Nyasaland (Malawi). Every now and again Mike would stop his car in the middle of the bush to take a break from the difficult, long distance driving. He would often notice something shining, or an agat...


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Working With Diamond

Posted by Site Moderator Webmaster on Tuesday, May 23, 2017, In : Faceting 

Duncan Miller

No, this is not about polishing diamonds, which in South Africa is illegal without a license, but about working with diamond grit or paste. For the coloured stone gem cutter, diamond paste is easier to source and to use. Loose grit and pastes are available in a range of mesh sizes, with crushed natural diamond or synthetic diamond. Synthetic diamond is made as single crystals and polycrystalline aggregates. The polycrystalline diamond breaks down with use to produce finer parti...


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