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Fakes & FraudsDoctored cuprite

26th Dec 2018 19:16 UTCReiner Mielke Expert

https://www.mindat.org/photo-927942.html judging by the luster ,rounded edges and other attached cuprites I would say that this crystal has been polished.

26th Dec 2018 19:42 UTCPaul Brandes 🌟 Manager

The description does state "Malachite has been removed from the crystals..."

I assume the best way to do this is to polish/buff them off?

26th Dec 2018 19:44 UTCJolyon Ralph Founder

This treatment is typical for crystals from this locality.

26th Dec 2018 20:38 UTCReiner Mielke Expert

I doubt if the polishing was to remove malachite since the attached crystals are not polished and have no malachite on them. Seems to me someone thought they would be able to make the cuprite look better by removing the malachite and ended up with a rough etched looking crystal like the attached ones. To correct this mistake they decided to polish the face to look more like what they thought it should have looked like after removing the malachite. I call that compounding a mistake and a fake specimen.

26th Dec 2018 20:53 UTCJolyon Ralph Founder

You have absolutely no way of knowing that Reiner.

I can give you an alternative explanation.

The original specimen had various faces physically polished to reveal the cuprite underneath the malachite.

Later, a more experienced dealer was able to remove the remaining malachite from the specimen chemically.

As the description clearly states that the malachite was removed you cannot make accusations such as that because you simply do not have any evidence to back your 'theory' up.

26th Dec 2018 21:27 UTCReiner Mielke Expert

You are right it is just a theory but more plausible than yours. After all why would someone polish off malachite when they could easily remove it chemically? However either way, polishing faces on a crystal in my opinion results in a fake crystal. Furthermore polishing was not mentioned in the description so it is misleading.

26th Dec 2018 21:45 UTCPaul De Bondt Manager

The crystal looks weird tough.

The under right crystal edge is sharp while the others are rounded.

And it seems that the upper face and upper right crystal face have been shaped out of massive cuprite.

Look at the top face, seems that the left part is curved toward the top while it should be straith.

The crystal has not the same lustre than the other crystal below.

Even experienced collectors and dealer can be fooled !

27th Dec 2018 07:09 UTCJolyon Ralph Founder

> After all why would someone polish off malachite when they could easily remove it chemically?

You're assuming every small dealer/collector/miner in Namibia is knowledgeable in chemistry and knows what acids are suitable (or has them available).

27th Dec 2018 10:49 UTCBruce Cairncross Expert

I can add my opinion for what it's worth and suggest perhaps none of the above apply. I have a variety of cuprite specimens from Onganja dating back to the 1970s. Most still have the malachite coating, one has been chemically cleaned to reveal a heavily pitted, cuprite surface ( see example in the Namibia I book, page 327). In rare instances natural cuprite was found at Onganja with no malachite coating. I have one specimen very similar to the Arkenstone specimen discussed above. Mine is a small crystal on calcite matrix having undergone no chemical or abrasive treatment and it looks extremely similar to the one above. Rounding of the crystal edges does not necessarily prove polishing as some Onganja cuprites can be rather crudely formed and not sharp- edged. So while the Arkenstone specimen might have been polished / brushed / chemical treated it could be natural.

One question: why is the locality given as Ogonja and not Onganja?

27th Dec 2018 11:16 UTCDebbie Woolf Manager

I think it was polished after chemical use to hide the pitted marks. I visited a major dealer in Windhoek and seen this, even have a Tsumeb azurite specimen just like this.

28th Dec 2018 00:05 UTCDebbie Woolf Manager

> why is the locality given as Ogonja and not Onganja?

Jolyon/David can you please look at the full locality history log, entries, dates and minerals are out of sync.

28th Dec 2018 01:23 UTCKeith Compton 🌟 Manager

Often wondered about the alternative spellings as it seems that Mindat is the only place to have this. I certainly couldn’t find a source for the shortened name.

28th Dec 2018 01:32 UTCDoug Daniels

Might be good to have the alternate spellings included (maybe they already are?). That way, if we have a specimen with an odd spelling of the locality, we could find the currently accepted spelling. Of course, some may always argue...

28th Dec 2018 05:47 UTCKevin Conroy Manager

Doug, I must disagree, unless you want to see names like Stumeb on Mindat.

28th Dec 2018 18:49 UTCDoug Daniels

Well, something like Stumeb, no. I was looking at the example above - Ogonja/Onganja. One is misspelled, but different dealers may use either one, even though they are referring to the same location. Sometimes a result of translation from one language to another, and then maybe from that one to yet another, and so on. Unless someone can verify for certain the name of the location, and then enter into the page something to the effect "location sometimes erroneously referred to as...".

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