* TSX up 10.47 points at 11,678.23
* Eight of 10 sectors higher (Updates with details, comments)
By Claire Sibonney
TORONTO, July 23 (Reuters) - Toronto's main stock index hovered around the unchanged mark on Friday morning in volatile trading as robust North American earnings were offset by worries ahead of European bank stress test results.
Sentiment benefited from a fresh batch of solid corporate results, including U.S. heavyweights Microsoft Corp (MSFT.O) and Ford Motor Co (F.N), while positive economic data in Europe also helped ease fears about the strength of a recovery.
On the domestic earnings front, Canadian National Railway (CNR.TO) rose 0.9 percent to C$64.28 after it reported a 38 percent jump in quarterly profit on Thursday and raised its full-year forecast. [ID:nN22122933]
"(Earnings) have been very positive for the market ... There's been a smaller set of Canadian numbers, but the CN Rail numbers have caught attention and have been positive for the market," said Fergal Smith, managing market strategist at Action Economics.
At 10:38 a.m. (1438 GMT), the Toronto Stock Exchange's S&P/TSX composite index .GSPTSE was up 10.47 points, or 0.1 percent, at 11,678.23. Eight of the 10 sectors were higher.
Also on the plus side for riskier assets, data showed Britain's economy grew almost twice as fast as expected in the second quarter and German business sentiment leaped by a record margin in July. [ID:nLDE66M0RN] [ID:nLDE66M0JV]
But equities were choppy as markets tracked the euro, which slipped against the U.S. dollar as doubts grew that the stress tests of European banks, due at noon EDT (1600 GMT), won't reveal the true health of financial institutions. [FRX/]
"The euro has fallen out of bed ... European stress tests are going to be the big focus of the morning and euro/dollar is a big tracker of that risk," said Smith.
"There have been reports that sovereign debt defaults are not part of the criteria being used for the stress tests so that will take some of the credibility away."
The uncertain investor sentiment weighed on oil prices, with crude drifting lower after hitting a three-month high near $80. [O/R]
Heavily weighted financial shares were little changed while the materials sector was up slightly.
Dragging the technology sector down, contract electronics manufacturer Celestica Inc (CLS.TO) fell 3 percent to C$9.13 after reporting a quarterly net loss, hurt by higher restructuring charges. [ID:nSGE66M0EC]
$1=$1.04 Canadian Reporting by Claire Sibonney; editing by Rob Wilson