Apple shares dip below $600 mark, climb

• Investors displeased with big earnings miss
• CNBC: White iPad Mini pre-orders sold out within hours
• Concerns remain about current quarter revenue, narrowing margins

Apple (AAPL) shares traded below $600 in afternoon trading Friday before later climbing above that benchmark, a day after the company reported that its fourth-quarter earnings missed expectations. Investors seem worried about the rising costs of production for its devices and that the company has missed profit estimates for the second straight quarter.

It's the first time the world's most valuable company has seen its shares fall below $600 in three months.

The stock ended the day's trading session at $603.97, down $5.57 or 0.9%.

Apple shares have dropped more than $100 from their record high of $705.07, hit on Sept. 21, the day the iPhone5 went on sale in the U.S. and eight other countries.

That's a total loss to investors of $106 billion, although Apple's total market capitalization of $556 billion means it's still the largest company on earth, by a wide margin.

Apple said profits for the rest of the year would fall from last year because it's launching so many new products. It's expecting mammoth sales, but new products are more expensive to make than older ones. The higher production costs are squeezing its margins.

Apple launched the iPhone 5 a month ago and unveiled two new iPads and three new Macs this week. In addition, it's shipping new iPods.

Wall Street analysts took the adjustment in stride, knowing that Apple nearly always lowballs its estimates, but several cut their earnings estimates for the fiscal year that started this month.

Stuart Jeffrey noted that Apple's profit margins should be back to normal in the quarter that starts in April, but that will be too late to fully make up for the earnings hit in the holiday quarter. He cut his earnings estimate for the year 10% and his price target on the shares from $710 to $660.

The Cupertino, Calif.-based company started taking orders for the iPad Mini on Friday. The new, smaller version of the iPad tablet starts at $329. Initial shipments of the white model quickly sold out on Apple's site; buyers now will now have to wait two weeks for delivery. The black model was still available midday Friday for a one-week delivery.

Concerns remain about Apple's earnings prospects for the current quarter, its critical first quarter of fiscal 2013. Apple's forecast for the holiday period is lower than what analysts had expected.

Apple is estimating quarterly revenue of $52 billion while analysts on average were expecting $55 billion.

Analysts also had expected the quarter would be powered by strong sales of the iPhone 5 and the iPad Mini.The $329 Mini, a 16 gigabyte, Wi-Fi-only model, is still scheduled to go on sale in Apple stores Nov. 2.

The Mini and a new full-size iPad that Apple launched Tuesday faces competitive headwinds as a bevy of tablets and smartphones hit the market in coming days and weeks.

Microsoft's Windows Surface tablet went on sale today. And Amazon Kindle Fire HD, its 8.9-inch tablet, starts shipping Nov. 20.

Microsoft and Google also are announcing new smartphones Monday, based on their respective Windows Phone and Android mobile operating systems.

Contributing: The Associated Press.