Exhibit 32(b)
CERTIFICATION PURSUANT TO
18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002
In connection with the Annual Report of Cliffs Natural Resources Inc. (the “Company”) on Form 10-K for the year ended December 31, 2009 as filed with the Securities and Exchange Commission on the date hereof (the “Form 10-K”), I, Laurie Brlas, Executive Vice President and Chief Financial Officer of the Company, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that, to such officer’s knowledge:
| (1) | The Form 10-K fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 (15 U.S.C. 78m or 78o(d)); and |
| (2) | The information contained in the Form 10-K fairly presents, in all material respects, the financial condition and results of operations of the Company as of the dates and for the periods expressed in the Form 10-K. |
Date: February 18, 2010
| By: | /s/ Laurie Brlas | |
| Laurie Brlas | ||
| Executive Vice President and Chief Financial Officer |