Gold prices came under pressure on Monday after the U.S. and five other world powers reached an historic agreement with Iran that would roll back that country’s nuclear program. With the threat of any imminent conflict with Iran eased for the short term, February gold GCG4 -0.45% was down $3.20, or 0.3%, to $1,241.40 an ounce. March Silver SIH4 -0.71% was down 11 cents, or 0.5%, to $19.80 an ounce. Gold could stay under pressure for awhile, according to Yves Lamoureux of market advisory firm Lamoureux & Co., who said the Iran deal is “very negative” for gold and that it will finally “set the stage for a bear ... (full story)