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 Post subject: 95-carat, Type IIa diamond found in Angola
PostPosted: Wed Jan 29, 2014 12:28 pm 
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Courtesy of National Jeweler:
http://www.nationaljeweler.com/diamonds ... 2541.shtml
Quote:
Perth, Western Australia--Mining company Lucapa has unearthed a 95.45-carat diamond from its Lulo Diamond Concession in western Angola, the second-largest stone recovered to date at the alluvial deposit.
Image

The company notes that the diamond has not been cleaned, and that is expects its appearance and clarity to improve dramatically after iron staining is removed.

Currently, the diamond’s color is classified as D/E.


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 Post subject: Re: 95-carat, Type IIa diamond found in Angola
PostPosted: Wed Jan 29, 2014 1:26 pm 
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Hello Barbra,

Impressive.

What is the meaning of "iron strainig"? Treatment by heating or radiation or else?

Brigitte


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 Post subject: Re: 95-carat, Type IIa diamond found in Angola
PostPosted: Wed Jan 29, 2014 1:50 pm 
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They will use acid if staining is on outside. Heating or irradiation does not remove iron oxides.

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 Post subject: Re: 95-carat, Type IIa diamond found in Angola
PostPosted: Sun Feb 02, 2014 7:51 pm 
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'iron staining' means that a thin layer of iron oxides/hydroxides minerals has naturally coated the diamond surface and impregnated surface reaching fractures, which makes the diamond appear brownish-yellow, but this staining will be removed by dissolving it in acid, in order to reveal the actual clarity of the diamond itself.


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