If they are more successful than some analysts expect, gold could fall.
Gold fell below $400 an ounce, from a high of $800 in 1980.
Gold last week fell below $400 an ounce for the first time in 19 months.
Gold fell $10, to $412.90, and the dollar was mostly higher.
Gold, above $400 an ounce in July, fell below $350 last week.
On Wednesday, gold fell below $400 an ounce for the first time in 19 months.
Gold for current delivery in March fell $1.90, to $363 an ounce.
Gold, which had been $500 an ounce early in the year, fell to the low $430's and oil prices went below $16 a barrel.
The dollar rose against most major currencies, while gold fell.
Gold, which had reached its highest prices since early 1983 on Monday, fell sharply.