Important private archive in $5 million offering.
A large and important private collection of rare books, colonial art and early photographs, worth up to $5 million, is about to hit the market - including 10 historic watercolours depicting Indigenous Australians.
Acquired over 50 years by Melbourne book enthusiast Denis Joachim, some are claiming it will overshadow all but the bigger state collections and is certain to attract institutional as well as private buyers. 
Mr Joachim worked with his father in the import-export business before turning to property development. His first acquisition at age 18 was an antique book on Australia colonial history from a bookshop in Dandenong, Victoria.
The collection - which once occupied a series of grand custom-made cabinets in his former home in Toorak - has been in storage for the last few years while negotiations with auctioneers on its potential sale have continued.
Among the more than 1000 lots is an extensive offering of early Australian voyage and natural history books plus drawings and watercolours by colonial artists such as Conrad Martens, Samuel Thomas Gill and   Augustus Earle.
Even specialist rare book dealer Jonathan Wantrup, who has known Mr Joachim for 40 years and helped him with many of his acquisitions, was surprised by the collection.
"Until I saw it I didn't realise how extensive it was," he said.
Mr Wantrup, a director of Australian Book Auctions, has been working with auctioneers Mossgreen on the massive catalogue of the collection, which will be offered for sale in Melbourne over three days, from   June 19 to 21. Highlights will be on view in Sydney on Sunday and Monday at Martyn Cook Galleries in Rushcutters Bay.
"Once you see it, you see how good it is. Apart from major institutions, I suspect no other collection would have as much," Mr Wantrup said.
The collection includes what are regarded as the first series of drawings of Indigenous Australians, attributed to John Heaviside Clark around 1813, which are believed to have been used for the book Field Sports of the Native Inhabitants of New South Wales. The pictures show Aborigines hunting, fishing, having a corroboree, a war party and a night scene in a camp. As Mr Wantrup said, Indigenous Australians are shown in a favourable light, in contrast to later, often demeaning portrayals. "The picture is amiable and positive," Mr Wantrup said.
The 10 works were first offered as separate lots at Sotheby's London in 1987, and bought by London art dealer Angela Nevill, who often acted for the late entrepreneur Alan Bond. They were offered again as one lot at Sotheby's in Melbourne in   April 1993 on behalf of Dallhold, one of Bond's companies. At Mossgreen they are described as "price on request" but Mr Wantrup said a figure in the hundreds of thousands would be near the mark.
In addition to the original paintings, the book Field Sports, containing the 10 hand-coloured aquatints based on the same images, is also included in the Joachim sale for $1500 to $2000.
Among the important photographs is Olaf Blackwood's Panorama of Sydney & Harbour from Government House, formed of 12 large albumen prints in a leather album dating from around 1858. Among the earliest panoramas of Sydney, it is estimated at $60,000 to $80,000. At the time, Blackwood had established a studio in Woolloomooloo. It was the first and largest such view seen in the colony and won praise from the Sydney Morning Herald.
Also on the sale is the Album by W. Blackwood of Australian Scenery - 12 large-format views including the Great Southern Railway Station, Campbells Wharf, and Farm Cove and Government Garden.
Another important panorama is Major James Taylor's 1.85m-wide colour aquatint view of Sydney in 1823, a view out to the heads and west towards the Blue Mountains.
Numerous photos of Melbourne and South Australia are included in the library of Lord and Lady Loch, housed in a number of albums. Lord Loch served as governor of Victoria from 1884 to 1889. His collection came on to the London auction market in the 1980s, bundled into tea chests, when Mr Joachim heard about it and pounced.
Early exploration and botanical books, along with photos and prints, comprise about half the 1046 lots on offer.
Among the rarest works is a first edition of John Fielding's An Historical Narrative of the Discovery of New Holland and New South Wales, London 1786. Written before the first settlement, this is the first separate account of NSW. It is estimated at $12,000 to $24,000.
John Lewin's Natural History of Lepidopterous Insects of New South Wales from 1805 is a rare specially coloured edition on large paper of which there were only 40 copies. It is estimated at $40,000 to $60,000.
No collection of early illustrated botanical works is complete without a copy of James Smith's A Specimen of the Botany of New Holland, with 16 hand-coloured plates including the stunning image of the waratah. Mr Joachim's copy of the first separately published book on Australian botany, a first edition from 1793, is estimated at $20,000 to $30,000.