Gold for December delivery rose on the Comex division of the New York Mercantile Exchange Thursday, as the dollar index dropped sharply. The dollar index added 0.73 percent to 79.33 on the International Exchange. With the dollar\'s help, gold added $13.40 to $1,793 per troy ounce. Silver gained 36 cents to $35.05 per troy ounce. A troy ounce is 0.083 pound, instead of the standard ounce, which is 0.0625 pound. The euro rose to $1.3017 from Wednesday\'s $1.2905. Against the yen, the dollar fell to 78.47 yen from 78.49 yen. The British pound rose to $1.6193 from $1.6096. The Australian dollar rose to $1.0244 from Wednesday\'s $1.0218. The dollar fell to 0.9803 Canadian dollars from 0.9879 Canadian. The dollar also fell to 7.7544 Hong Kong dollars from 7.7559 HKD.