Sienna Resources Inc V.SIE

RE: Kinross Buys the rest

[Oilseeker]

Toronto, Ontario, March 11, 2010 – Kinross Gold Corporation (TSX: K, NYSE: KGC) and Underworld

Resources Inc. (“Underworld”) (TSX-V: UW) announced today that they have entered into a letter agreement

whereby Kinross would offer to acquire 100% of the outstanding common shares of Underworld (the “Common

Shares”) by way of a friendly take-over bid, other than the 8.5% of the Common Shares already owned by Kinross

(on a fully-diluted basis). Subject to the execution of definitive agreements, the board of directors of Underworld

unanimously recommends the offer to its shareholders and the directors and management team have agreed to

tender their shares to the offer. Pursuant to the terms of the letter agreement, Underworld has agreed to work

exclusively with Kinross toward the conclusion of a definitive support agreement which is anticipated to be

executed and delivered by the parties by March 15, 2010.

Highlights of the proposed transaction

? For each Common Share of Underworld, Kinross will offer 0.141 of a Kinross common share, plus
.01

in cash. The offer represents an implied offer price of approximately $2.62 per Common Share, based on

the March 10, 2010 closing price of $18.54 per Kinross common share on the Toronto Stock Exchange

(the “TSX”). The transaction values the fully-diluted share capital of Underworld at approximately $139.2

million.

? The offer represents an attractive premium of 36.0% over the closing price of the Common Shares on the

TSX Venture Exchange (“TSX-V”) on March 10, 2010, the last day of trading prior to announcement of

the offer, and a premium of approximately 50.2% based on the volume-weighted average prices of the

Common Shares and Kinross’ common shares, for the 20 trading days ended March 10, 2010.

“The offer will provide Underworld shareholders with immediate value for Underworld’s current assets and future

growth potential,” said Kinross President and Chief Executive Officer, Tye W. Burt. “It will also give Underworld

shareholders the opportunity to participate in a senior gold producer with a proven track record and significant

upside potential as we advance the next wave of our growth program. We have great respect for Underworld’s

management and employees, and their efforts to advance the White Gold project to its current stage of

development.”

Full details of the offer will be included in the formal offer and take-over bid circular (the “Circular”) expected to be

mailed to Underworld shareholders shortly after definitive agreements have been entered into between Kinross

and Underworld. The offer will be open for acceptance for at least 35 days following the commencement of the

offer. The offer will be subject to several conditions, including acceptance of the offer by the holders of at least

two-thirds of the outstanding Common Shares (calculated on a fully-diluted basis) and the receipt of all necessary

regulatory approvals. It is expected that if Kinross acquires at least two-thirds of the outstanding Common

Shares, Kinross intends to take steps to acquire all outstanding Common Shares not acquired pursuant to the

offer. If 100% of the Common Shares are tendered, Kinross will issue approximately 6.8 million common shares

pursuant to the transaction (based on the fully-diluted share capital of Underworld), representing approximately

1.0% of Kinross’ current outstanding common shares.

Underworld is a junior exploration company focused in Canada. Underworld’s key asset is the White Gold project,

located in the Tintina gold belt, approximately 95 km south of Dawson City, Yukon Territory.

Year of the Profit, Oilseeker