ADDENDUM TO OPTION AGREEMENT UNDERSHIL AIMAG (“ALTAN”) PROPERTY

EXHIBIT 10.13

ADDENDUM TO OPTION AGREEMENT
UNDERSHIL AIMAG (“ALTAN”) PROPERTY

THIS ADDENDUM is made effective as of the 4^th day of November, 2004.

BY AND BETWEEN:

MONGOLIAN EXPLORATIONS LTD. ("Mongolian"), a Nevada Corporation
whose address is 000 Xxxx Xxxxxx Xxxxxx, Xxx. 0000, Xxxxxxxxx, X.X., X0X 0X0

&

     TON FEI XXXX XXXX & ASSOCIATES (“Tham”)
whose address is 0000 Xxxx 00^xx Xxxxxx, Xxxxxxxxx, X.X., Xxxxxx, X0X 0X0

WHEREAS:

1)	This addendum does not supercede or override any previous addendum unless specifically stated herein.
2)	Due to:
	(a)	Rio Minerals Limited's unavailability to perform the exploration work program as previously scheduled by December 31, 2004;
	(b)	the upcoming inclement weather conditions in Mongolia; and
	(c)	the ongoing attempt of Mongolian to obtain its Registration Statement "effective" status with the U.S. Securities and Exchange Commission regarding its filing of the SB-2 Registration Statement;
	(d)	and as a consequence, to raise the necessary capital in a timely manner which has caused Mongolian to amend the Option Agreement; and

WHEREAS:

Pursuant to Section 2 of the Option Agreement dated September 1, 2003, and by an Addendum to the Option Agreement dated June 15, 2004, Mongolian was required to incur the following exploration expenditures:

	(a)	(ii) (2) $26,444 on or before December 31, 2004;
	(b)	(ii) (3) $50,000 on or before December 31, 2005; and
	(c)	(ii) (4) $100,000 on or before December 31, 2006.

NOW, THEREFORE:

BE IT RESOLVED,

Section 2 of the Option Agreement dated September 1, 2003, and by an Addendum to the Option Agreement dated June 15, 2004, shall be amended in the following manner:

	(a)	(ii) (2) $26,444 on or before July 31, 2005
	(b)	(ii) (3) $50,000 on or before July 31, 2006; and
	(c)	(ii) (4) $100,000 on or before July 31, 2007.

IN WITNESS WHEREOF, this Addendum to Option Agreement dated November 4, 2004, has been executed by the parties hereto as of the day and year first above written.

MONGOLIAN EXPLORATIONS LTD. /s/ Xxxx Xxxxx		TON FEI XXXX XXXX & ASSOCIATES /s/ Ton Fei Xxxx Xxxx
By: Xxxx Xxxxx, President, Director		Ton Fei Xxxx Xxxx