This week’s annual Reuters Global Mining and Steel Summit has been a pretty rich event.

Oh, the guests have been stellar, for sure, but there’s also been a lot of talk about gold and jewelry and the prospect that maybe someday this lousy economy will turn around.

For Peter Marrone, chief executive of Yamana Gold, customers’ willingness to buy jewelry is an important consideration in providing outlook for his company.

But even with times so tough, jewelry sales are an inexact science, he warned. And overall gold demand is less a matter of whether someone is willing to shell out a couple hundred dollars on a new necklace and more based on investors looking for safe-haven investments in times when other investments are far shakier.

Marrone was one of the featured speakers at the summit, which continues through Thursday in New York, London and Sydney. The Summit program is in its fifth year, and in 2009 will include top-level executives from  industries and sectors including everything from Infrastructure; to Global technology; to Investing in India, China, Japan and Russia; to Islamic Banking.

The Summits continue next week at the annual Global Food and Agriculture Summit with guests in the U.S. and Asia from March 16-19; and the Funds Summit in Luxembourg on March 17-18.