By Claudia Assis
SAN FRANCISCO (MarketWatch) -- Optimism that Europe will be able to stave off its sovereign-debt crisis in the eve of a summit carried gold and oil futures higher on Tuesday. The commodities extended previous session's gains as well. Crude for December delivery CL1Z +2.22% added $1.80, or 2%, to $93.11 a barrel on the New York Mercantile Exchange. Gold for December delivery GC1Z +0.28% added $3.40, or 0.2%, to $1,655.40 an ounce on the Comex division of the Nymex. Most base metals, however, traded lower, with copper receding 0.6% after Monday's 7% rise.
