The Old Stump, Lake Superior is the sketch Lawren Harris completed for his masterpiece North Shore, Lake Superior. (Heffel Fine Art Auction House)

An oil sketch by Group of Seven member Lawren Harris sold Thursday at a Toronto auction for $3.5 million, the second highest amount ever paid at auction for a piece of art in Canada.

Harris's 30-by-38-centimetre sketch, called The Old Stump, Lake Superior, was done for one of the artist's most important paintings, North Shore, Lake Superior, which hangs in the National Gallery of Canada in Ottawa.

Three other Harris works went for over $1 million each — after factoring in a 17 per cent buyer's premium — including Houses, St. Patrick Street, which went for $2.8 million.

"Lawren Harris was one of the truly great North American painters of the first half of the 20th century and Harris deserves the values that we see at auction," said Robert Heffel, who runs the Heffel auction company with his brother, David Heffel.

Harris was not the only big seller. A Tom Thomson painting, Early Spring, Canoe Lake, sold for almost $2.75 million, which, according to the Heffel auction company, is the most ever paid for a Thomson painting.

Proceeds from the sale of the Thomson painting will be donated to charities by an anonymous Canadian philanthropist, along with the proceeds from seven other works, said Robert Heffel.

Tom Thomson's Early Spring, Canoe Lake, painted just a few months before his death in 1917, sold for $2.75 million. (Heffel Fine Art Auction House)

The Heffel brothers had predicted Thursday would be a big night, based on a slate of 15 especially impressive works that were up for sale.

"Going into the auction we knew the quality was so strong and … when you get paintings that are groundbreaking paintings, then the normal rules don't apply," said Robert Heffel, moments after the Harris works were sold.

He said Thursday's auction proves the recession hasn't put much of a damper on the Canadian art market, which "remains very strong."

Those works were put on the auction block by the estate of Helen E. Band. She was the daughter of Canadian art collector Charles Band, a longtime friend of Harris.

Charles Band also shared correspondence with the artist's contemporaries, including A.Y. Jackson, Arthur Lismer, Frederick Varley and Emily Carr.

Heffel brought in a total of $20.8 million in Thursday's sale, including $10.5 million from the Band collection.

Among the Group of Seven works that changed hands:

• Lawren Harris, Iceberg, Baffin's Bay North, $1,521,000.
• Lawren Harris, In Buchanan Bay, Ellesmere Island, $1,111,500.
• Frederick Varley, Nude on a Couch, $585,000.
• A.Y. Jackson, North Shore, Lake Superior, $526,500.
• Tom Thomson, Autumn, Algonguin Park, $380,250.

An abstract oil by Paul-Emile Borduas, Arabesque, sold for $338,750 and a painting by E.J. Hughes set a record, selling for $245,700.

The most expensive painting to sell at auction in Canada is still Paul Kane's Scene in the Northwest: Portrait of John Henry Lefroy, which went for $5.06 million in 2002, including a buyer's premium.