Cold weather has pushed natural gas prices sharply higher this week, and analysts say the gains could continue.
On Friday, natural gas futures ended slightly lower. The actively traded January contract edged down 2 cents to $4.12 per 1,000 cubic feet. It is still up 4 percent this week, and hit a six-month high on Thursday.
Half of all homes in the U.S. use natural gas as a heating source, making it by far the most popular source of heat in the country.
In metals trading, gold fell $2.90 to $1,229 an ounce, and silver fell 5 cents to $19.52 an ounce.