CHOP [China Gerui Advanced Materials] SC 13G/A: SCHEDULE 13G (Amendment No. 1)* China Gerui Advanced
[SCHEDULE 13G (Amendment No. 1)* China Gerui Advanced Materials Group Limited (formerly known as China Opportunity Acquisition Corp) (Name of Issuer) (Title of Class of Securities) G21101111 (CUSIP Number) December 31, 2009 (Date of Event Which Requires Filing of this Statement) o þ o * The remainder of this cover page shall be filled out for a reporting person’s initial]