* FTSEurofirst 300 falls 0.3 pct, still up 1.9 pct on week
* Miners retreat alongside metals prices as dollar rises
* Spanish, Portuguese stocks hit by nagging debt worries
By Blaise Robinson
PARIS, Jan 7 (Reuters) - European stocks were down around mid-session on Friday, as a stronger dollar ahead of key U.S. jobs data prompted investors to book profits from red-hot metals prices and heavyweight mining shares.
Nagging worries over the debt of several euro zone peripheral economies ahead of next week's key bond auctions continued to hurt Spanish and Portuguese stocks.
At 1150 GMT, the FTSEurofirst 300 index of top European shares was down 0.3 percent at 1,143.85 points, snapping a four-day winning run.
The benchmark index, which gained 7.3 percent in 2010, was on track to record a 1.9 percent gain on the week, its best weekly performance since early November.
The mood was less positive in peripheral Europe on Friday, with Spain's IBEX 35 down 1.4 percent and Portugal's PSI 20 down 1.2 percent.
After losing 17 percent in 2010, the IBEX 35, home of European bellwethers such as Santander and Repsol, is already down 3.1 percent this year.
The Peripheral Eurozone Countries Index was down 1.1 percent on Friday.
"The rising yields at debt auctions in the euro zone will continue to spook investors, and it's best to stay away from peripheral stocks such as Spanish and Portuguese banks until mid-year when the crisis should ease," said Arnaud Scarpaci, fund manager at Agilis Gestion, in Paris.
"For now, the safe bets are the main benchmarks such as the DAX and CAC, and the international exposure, with a little preference for the CAC because it has been lagging."
Bankinter was down 3 percent, Banco Santander off 2.1 percent and Banco Comercial Portugues 2.6 percent lower.
Higher-yielding euro zone bonds were also under pressure as concerns over upcoming debt sales in the region unsettled investors. Portugal, Spain and Italy are scheduled to next week hold their first bond auctions of the year.
Mining shares also lost ground, with Xstrata down 1.9 percent, Antofagasta 1.8 percent lower and Anglo American off 1.7 percent, falling along with metal prices, hit by a stronger U.S. dollar and talk of tighter monetary policy in China.
GAME CHANGER
The dollar climbed to a four-month high versus the euro and a one-month high against a basket of currencies on Friday ahead of the U.S. jobs data.
That data is expected to show U.S. nonfarm payrolls rose by 175,000 in December, a Reuters poll signalled.
"Apart from the headline number, the focus will be on the change in earnings per hour. Rising wage inflation could be a game changer for the Federal Reserve and force it to raise rates sooner rather than later," Agilis Gestion's Scarpaci said.
Despite lingering worries on the euro zone debt crisis, Citigroup Global Markets strategists remained bullish on equities, saying European stocks should at least track earnings growth in 2011.
"Risks, if anything, look to be on the upside," the strategists wrote in a note.
"Equities do look fair value to cheap, rather than expensive, to us on most absolute and relative valuation measures.
"Money looks cheap with global real rates negative ... Capital allocators still don't like European equities, but there are signs the sellers are becoming harder to find. A return of appetite for the asset class could help to drive a re-rating."
(Reporting by Blaise Robinson; editing by David Hulmes)