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Fakes & Frauds"Gold" in BIF from Brazil

30th May 2016 00:12 UTCRicardo Scholz

Dear Friends,

My name is Ricardo and I´m a professor in Ouro Preto University in Brazil.

I would like to warn you about some samples of Banded Iron Formation with gold from Brazil. Recently a very careful seller came to me with some samples. I analysed some samples by SEM/EDS and I found a mixture o Cu, Zn and some other methals that shows typically brass. Latter I will attached the SEM images.

Please, dont stop to collect Brazilian minerals, but take care with some very anusual material.

All the best.

30th May 2016 02:29 UTCMaggie Wilson Expert

Thank you for the warning.

30th May 2016 15:45 UTCRicardo Scholz

Folks,

here you can see the EDS data.

All the best.

30th May 2016 18:19 UTCPavel Kartashov Manager

Dear Ricardo,

is it superficial contamination by technogenic brass? In other words, is presented this metallic phase inside ore specimens? Did you cut/sawe this ore?

It seems to me, that this is quite recent contamination (probably intentional). Magnetite ore is oxidized (rusty), while brass is fresh without secondary copper or zink minerals at its surface.

Kind regards,

Pavel

30th May 2016 20:09 UTCRicardo Scholz

Hello Pavel,

I saw two cut samples and gold (or brass!!!) is only on the surface. For me it is intentional. In the past, I also analyzed a sample and the result was gold, but I'm not sure if it's real or fake. It's not so hard to find small gold nuggets and with a small hammer to produce such crafts.

30th May 2016 21:26 UTCPavel Kartashov Manager

Thank you, Ricardo.

For me personally, a new find of native alpha-brass would be much more interesting than one more find of gold. But apparently this is not the case...

30th May 2016 23:30 UTCRicardo Scholz

Hello Pavel,

no, this is not the case, unfortunately. But I hope Brazil will continue to produce good torumalines, gold nuggets, new minerals....

31st May 2016 00:54 UTCAntonio Romano

I saw the material, it was obviously faked. Unfortunately, many of these uglies pebbles are currently sold to tourists in the XVIII th century historical towns of Minas Gerais state.

Just to remember, another well known brazilian fake is the diamond glued conglomerate from Diamantina. The real material is very rare, 99% in the market are faked.

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