NEW YORK--Exchange operator CME Group Inc. (CME) reduced the amount of collateral required to trade the benchmark gold and silver futures contracts on Friday.

The CME, which owns the Comex division of the New York Mercantile Exchange, trimmed gold margins by 10% effective close of trading Monday, in a notice emailed Friday afternoon.

Speculative investors in the benchmark 100-troy ounce gold contract can now deposit $5,940 to open a position and maintain $5,400 of that to keep that position overnight. That's down from the previous initial margin of $6,600 and maintenance margin of $6,000.

The initial and maintenance margin requirements for producers or consumers of gold have been reduced to $5,400 from $6,000.

Trading margins on the benchmark 5,000-ounce silver futures contract were cut 9.1%. Speculators must now deposit $8,250 to open a silver futures position and maintain $7,500 of that overnight, down from $9,075 initial margin and $8,250 maintenance margin previously.

The initial and maintenance margin requirements for silver producers and consumers have been reduced to $7,500 from $9,000.

The CME last cut trading margins on both contracts in May.