A trove of Canadian art treasures — canvases uncovered after decades, paintings from key periods and highlights of the burgeoning post-war scene — will cross the block in Toronto during the fall auction season.

Prominent collections are being featured by Heffel Fine Art, which holds its sale on Thursday and includes 216 lots. A prominent Montreal collection is offering several of the auctioneer's most significant works, including Jean-Paul Riopelle's Grande Fête (painted during his coveted, early 1950s period), the life-sized Michael Snow sculpture Sideway (a piece from his Walking Woman series) and Jean Paul Lemieux's beloved canvas Nineteen Ten Remembered.

Featured on the cover of Heffel's catalog, Nineteen Ten Remembered is the sale's most valuable offering for several reasons, explained auction house vice-president Robert Heffel.

Never before offered at auction, the nostalgic painting depicts the Quebec artist himself as a child, standing between his parents, and is arguably Lemieux's most famous work. It has been included in major Lemieux exhibitions and reproduced in books and publications about the artist — in fact, many raised in Quebec recall growing up with a poster or print of Nineteen Ten Remembered on their wall, Heffel said.

"We set the record for Jean-Paul Riopelle in auction (for Il était une fois une ville, sold in 2006). For a contemporary work of art auctioned in Canada it's Jean-Paul Riopelle, $1.6 million. We feel that Nineteen Ten Remembered can challenge that," he told CBC News.

Opening French hotelier François Dupré's bank vault to see the former Ritz-owner's long-hidden collection of Canadian impressionist art was 'like Christmas,' said Robert Heffel of Heffel Fine Art Auction House. Heffel

Another interesting collection that's piqued interest is that of French hotelier François Dupré, who took ownership of Montreal's Ritz-Carleton in the late 1940s. An aficionado of impressionism, he purchased works by Canadian Impressionists such as Clarence Alphonse Gagnon, James Wilson Morrice and Marc-Aurèle de Foy Suzor-Coté for display at the hotel. The whereabouts of his collection were unknown until his heirs recently came forward and revealed the works had been stored in a Montreal bank vault for the past 24 years.

"It's like Christmas and you're opening Christmas presents," Heffel said of uncovering the works.

"We go there, in this massive bank, and down below is the safety deposit box — very large. And we bring the paintings out and we see them for the first time. We'd seen a listing and things like that. But, oh it's exciting!"

The story behind the canvas

Interesting back stories are also behind several high-profile paintings for sale at Friday's Joyner auction, which is offering just over 200 works.

The Toronto-based firm's top lot is The Return from Town, an early Lawren Harris painting from 1911, the earliest point for Harris canvases. It marked the year he was elected to the Ontario Society of Artists as well as the year he met and started painting with J.E.H. MacDonald — an encounter that would lead to the formation of the Group of Seven nearly a decade later.

Expected to sell for between $500,000 and $700,000, The Return from Town — commissioned to accompany a story in Harper's Monthly magazine — contrasts "the tipsiness of the lumberjacks returning from their evening against that kind of still dignity of the landscape," said Joyner vice president Rob Cowley.

"You really do have a contrast that's interesting, that you don't always see, with people that are within the landscape," since the inclusion of figures is rare in Harris' works, he noted.

Another work Cowley singled out is William Kurelek's painting Handel's Messiah at Massey Hall, which depicts in great detail a performance of the Mendelssohn Choir at the historic Toronto venue. It is expected to fetch between $60,000 and $80,000.

"The most popular works at auction tend to be the works which have a personal connection for Kurelek and usually those works include those that depict his life," like his childhood in the Prairies or his adult years as a father in Toronto, Cowley said.

"He was really one of those artists who could convey the human spirit in his work."

Rising interest in post-war

At Joyner, as with rival auction houses Heffel and Sotheby's Canada, post-war and contemporary offerings have increased to represent half or close to half of the lots this season.

'It's a very exciting time for Canadian art at auction in Canada because you really are getting that same appreciation for post-war art that had already arrived for historical art'—Rob Cowley, Joyner Canadian Fine Art

"There's been more and more interest in the contemporary side of things... In many cases, you're now seeing the best examples by these artists at auction," Cowley said.

"It's a very exciting time for Canadian art at auction in Canada because you really are getting that same appreciation for post-war art that had already arrived for historical art, [for instance] with the focus on the Group of Seven."

At Heffel's spring 2011 auction, the contemporary sale surpassed that of the historical Canadian section — a first for the auctioneer. "It shows interest increasing in contemporary because this wasn’t the case a few years ago," Heffel said.

Reflecting this mounting awareness and focus on more contemporary artists, Sotheby's Canada is swapping the format of its Nov. 28 sale to start with post-war offerings and end with the historical Canadian artworks. Altogether, 186 lots will cross the block.

"There may be more excitement and more range in the contemporary area than we've had for some time," said Sotheby's Canada president David Silcox, a longtime champion of post-war and living Canadian artists.

He drew attention to artwork by members of the Painters Eleven, like Jack Bush's On The Nose (a "painting that pulsates with energy" and is estimated to fetch $60,000 to $80,000) and Kazuo Nakamura's "seemingly random but very highly structured" Core Waves No. 3 (expected to sell for $30,000 to $50,000), as well as influential Automatiste artist Paul-Émile Borduas' Blancs Méteaux (given a pre-sale estimate of between $175,000 and $225,000). A thickly layered abstract painting from 1955, the Borduas work is uncracked and in remarkable condition, after having been in the same collection for about 30-40 years, Silcox said.

Also garnering buzz is the painting depicted on the cover of the Sotheby's catalog: Country Club, which Lemieux painted in 1972, but hasn't been seen publicly since a 1974 international retrospective. Silcox described it as "heavenly."

He also highlighted several rare Morrice canvases depicting scenes from Venice and Avignon, a pair of David Milne works completed in the 1920s and an airy, abstract Harris from the late 1930s, likely painted during his time in Santa Fe.

In New York this fall, "Sotheby's did well in the modernist, impressionist and contemporary sales," Silcox said, noting that those recent sales were among the company's best ever for this time of year.

"I hope a little bit of that will rub off [on us]," he added. "I find that the general tenure from talking to people is that there's very little hesitation for the high-end, the really good works. I'm cautiously optimistic."