But it should not be inferred that sleepers, stirred by thoughts of arbitrage and strangers for auction rooms, barring Chinese antiques, are making an appearance again. Even small ones like this would be welcome among today's excitement-starved auction goers
Cotes come in many colours, to bend an expression derived from the story of Joseph in the Bible.
Bidding on the portrait, taken by Lawson's Martin Farrah, the company's managing director, was between two members of the local Chinese community in the room. Both said they were interested in the work because they liked it as a picture and were uninterested in the Cotes attribution, which has been worth as much as £457,250 for some works in the saleroom (Christie's 2012, for a double portrait).
The London trade was “happy” with the Lawson's work, Portrait of a Lady in a blue dress, half length with red curtain, holding a book ..and its cataloguing but sat on their hands, Mr Farrah said. Their reaction, when he spoke to them, was due to world gloom and doom he said.
The only other bid was an absentee at $8000, just short of the $10,000 to $15,000 estimate.
Although a “prominent antique dealer” had it for sale at $80,000 a decade ago, the jury is still out on the strength that should be given to its Cotes connection.
It was sold in a Vaucluse house which it was being emptied because the long term renter now needed to make a second down-sizing.
Mr Cook confirmed he was the dealer who previously had sought to place it but found would be buyers were unsure about the signature.
Australia has turned up many Cotes of different colours. There are a lot of would-be Cotes around, mostly not by his hand. Australia is or was the home for one of the most notorious of these.
A second was supposedly a portrait of one of the father's of Australian natural history Sir Joseph Banks.
Cotes, a very fashionable painter with a distinguished clientele, ironically did not always do the coats and dresses in his portraits.
They were by a drapery specialist by Peter Toms, so genuine pictures are also partly his.
Most of the suspect Cotes lack his grandeur and charm. These were not entirely absent from the Lawson specimen.
While he was a productive artist, Cotes, who came from a scientific background had only a short life. He died aged 44 in 1770.
With the auction stated to contain “only a few” lots", the 125 by 100 cm work was part of a collection which 10 years ago had been in a grand residence in Vaucluse Road.
Lawson's said this established and well regarded Eastern Suburbs family, was once again relocating.
Lawson's said many items were purchased “at fundraising auctions in and around Sydney and represent the altruistic nature of these collectors and benefactors.”
It was the National Gallery of Victoria that had to turn one of the “colourful” Cotes out into the cold of doubted attribution in mid 1970s when modern scholarship caught up with the specimen.
It does not appear to be on the gallery's website.
Melbourne's most celebrated curator of European paintings Dr Ursula Hoff had written in European Paintings Before 1800 published in 1967 that Portrait of a Flower Painter in the NGV collection as a Coates was “undoubtedly by Cotes.”
It was only the second time this notable writer seems to have erred. She is said to have told the owner of a painting by the American artist Harnett that it was of limited interest when presented for inspection in the 1970s.
Ten years after her lack of doubt on the gallery's "Cotes" Dr Edward Mead Johnson's Cotes Complete Edition with a Critical Essay and Catalogue listed the portrait as “among the most important of the pictures erroneously attributed to Cotes.”
The catalogue was published by the help of a grant by the august Paul Mellon Centre for Studies in British Art which normally might not have been expected to throw good money after bad.
The portrait was purchased through Christie's in 1922 and it would not be the first nor last work by Christie's to be challenged about its authenticity although only a fraction are.
“When Francis Cotes died in 1770 and his portraits were removed from the limelight of public exhibitions, his fame faded into oblivion," Johnson wrote in his catalogue.
“His pictures settled into the depths of country houses or lay hidden in secluded London drawing rooms” he added.
“It was not until the early 20th century when America came into prominence as an art market :that his work began to be widely noticed once again.
The reputations of many British artists were rescued as a result, Cotes among them.
But there were “a few genuine pictures and several hundred falsely attributed to him.” Most were owned by families which did not need to sell and given the chase for big glamour name artists like Gainsborough and Reynolds they were not sprung onto the market.
It now seems that anyone looking for a sleeper – or rather a work they can turn into one by successful arbitraging overseas a bargain – should look at dealer lists.
Dealers have always done a bit of trading between each other.
Late last year a collection of Hong Kong paintings, fully catalogued in an Asian Art catalogue of Sydney dealer Joseph Lebovic, reappeared in a catalogue published by Sydney antiquarian book seller Hordern House. The sale from one to the other was confirmed by both parties.
They were 15 watercolours by Edward Ashworth executed between 1844 and 1845.
The price remains on Mr Lebovic's archived on-line catalogue as "on application" and Hordern House would not say what they paid for them.
Mr Derek McDonnell for Hordern House said that the works had been offered at the Hong Kong Book and had been sold.
Hordern House in particular seems chuffed with the deal, Mr Lebovic not quite so. He was still unaware what Hordern House had asked for his sleeper.