Due Diligence at the Eleventh Hour?

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Lot# 45 Attica. Athens. Decadrachm, Estimate: US$875000

Attica. Athens. c. 465-460 BC. Decadrachm, 41.86g. (2h). Obv: Head of Athena right, wearing crested Attic helmet decorated with three olive leaves over spiral palmette and three-piece drop earrings. Rx: A - Θ - Ε Owl standing facing, wings spread; olive sprig at upper left; all within incuse square. Fischer-Bossert, unlisted dies. In itself, this coin is one of the finest of all Greek coins in existence. It is, according to Wolfgang Fischer-Bossert, one of three coins tied for the finest known, with only one of the other two being in private hands and the second in a museum, and it is one of the most significant issues ever struck by the Greeks. The head of Athena is struck in high relief. The smile produces an apple-cheek face, which blends with a slightly elliptical archaic eye. A fair amount of the crest is present and all of the pearls along the neck and under the helmet are complete, as well as full detail on all of the leaves, the helmet and the complete hairline and complete ear. The owl, which normally has large planchet defects in the chest, in this case is completely and fully struck, including the chest, the tail, and even the feet which are absolutely sharp. Only the very top of the A is off the flan and there is a tiny bit of corrosion in the right wing and an even smaller miniscule spot in the lower part of the left wing. Near Mint State. This coin was graded by NGC with a photo certificate, but not encapsulated. If the buyer requests the coin encapsulated, NGC will oblige. When NGC does register sets of ancient coins, the person owning this coin would no doubt have the number one register set. NGC Cert. #3443360-001. NGC Grade is Choice AU*, Fine Style, Strike 5/5, Surface 4/5.

The coin is proudly displayed on the cover of the catalogue of the US numismatic auction house that is selling this artefact:


But just recently (but not until after bidding had reached at least 700 000 dollars), this has appeared on the seller's website:

Lot# 45 Lot Withdrawn - This lot has been withdrawn from the auction. Recent new information has come to light which points to the possibility that the coin is not authentic. Further investigation and research is needed. Both Heritage and Gemini have the utmost responsibility to ensure the authenticity of every lot sold and our decision to withdraw this lot is in line with that policy. We regret this new information was only discovered at the eleventh hour and apologize for any inconvenience resulting from the withdrawal of this lot. We remain committed to only offering the very best coins, in which our clients can have full confidence when it comes to quality, authenticity and value.

They would have even more confidence if the coin could be traced back by a collecting history to the point when (and where) it left the ground, removing any uncertainty whether it was a genuine coin found in the ground, or one that had been knocked up in some workshop recently and passed off as one. As one collector has noted:

In the last few years a few mint examples of the Athenian Decadrachm have come to market. Interestingly, and alarmingly, they have all been mint examples and with no previously known die examples. And all have a lack of provenance. Red flags abound.[...] Be careful out there

( ...; otherwise you might end up buying looted stuff unawares". He might have added that last bit himself, but he did not).

So where did this coin "surface"? Why did the auctioneers not raise this question with the seller earlier, rather than waiting until the "eleventh hour"?

There are several mentions in the very long text about this coin in the seller's catalogue of Dr Wolfgang Fischer-Bossert's, The Athenian Decadrachm (NNM 168, New York 2008) and his 'More Athenian Decadrachms' (SNR 88 2009)" but not a single mention of this, the finest example above ground, being actually mentioned in those works... Did Fischer Bossert not know of its existence even though it had been (presumably) sitting in some "old collection" somewhere or other? The long text is about the "hubbing" method used to produce the dies of this coin "produced in an amazing way reminiscent of modern industrial procedures". Yes.

So, this person who was willing to pay upwards of 700 000 dollars to purchase this coin, did he do so only after extensive correspondence with the seller convinced him that the object really had been obtained licitly and had a perfectly good pedigree going back decades, or did he put forward the money regardless of where the object came from - only to be able to have "the number one register set" of ancient coins all to himself?
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