*Materials, energy issues buoyed by firm oil, gold
*Financials will continue "sloppy" trading
*Astral Media shares down after third-quarter results
TORONTO, July 10 (Reuters) - The Toronto Stock Exchange's main index was higher at midmorning on Thursday, yanked up by bargain-hunting in mining and oil shares after they tumbled on Wednesday.
The index's resource-laden materials sector led the gain, up 2.4 percent, on strength in underlying commodity prices, particularly gold, which has been a safe-haven buy amid tensions in the Middle East.
Oil and gas shares were higher, up 1.4 percent, as oil prices rose more than $2 on supply concerns and more Iranian missile tests.
At midmorning, the S&P/TSX composite index .GSPTSE was up 111.45 points, or 0.82 percent, at 13,722.29. The index jumped 100 points at the open, but quickly lost all that and turned negative before climbing back up again.
It tumbled nearly 200 points on Wednesday, hit by fears over the economic outlook and weaker second-quarter results.
John Ing, president of Maison Placements Canada, said concerns over the impact of rising oil prices and persistent worries over the health of the financial sector will continue to plague the market.
"All of this is contributing to a potent, toxic mixture for the markets," he said. "So, while we have a bounce today I think it's short-lived."
Financials, which have been battered by the impact of the credit crunch as well as persistent worries of more losses and writedowns, were down 0.4 percent.
"Financials stocks have been very sloppy and will continue to be sloppy as the overall mood is that the direction is down," Ing said.
Shares of Astral Media ACMa.TO were down C$1, or 3.2 percent, at C$29.95. The specialty-TV and radio group reported a 21 percent jump in third-quarter profit on Thursday, helped by recent acquisitions, but that was lower than expectations. ($1=$1.02 Canadian) (Reporting by Jennifer Kwan; Editing by Peter Galloway)