Rimfire and Northgate Commence Drilling at Boulevard, Yukon

    VANCOUVER, Sept. 23 /CNW/ - (All figures in Canadian dollars) Rimfire
Minerals Corporation, TSX-V:RFM, is pleased to announce that in partnership
with Northgate Minerals Corporation, TSX:NGX, drilling has commenced at its
new gold discovery on the Boulevard Property. The Boulevard Property is
located approximately 135 kilometres south of Dawson City, Yukon. Gold bearing
mineralization, including 7.04 g/t gold over 6.0 metres, was discovered in two
of three trenches over a 300 metre trend (see Rimfire news release PR08-12,
August 20, 2008). The diamond drilling program will consist of 4 to 6 holes
averaging 150 metres in length and is expected to be completed by mid-October.
    The current program was initiated after this summer's discovery of
gold-bearing mineralization in trenches testing anomalous
arsenic-antimony-gold soil geochemistry at the Boulevard. Chip sampling from
the first trench (TRBV08-01) yielded 7.04 g/t gold over 6.0 metres. One
hundred metres southeast, trench TRBV08-02 returned 6.43 g/t gold over 2.0
metres. Gold mineralization is hosted in strongly sericite-clay altered
schists with disseminated pyrite, arsenopyrite, stibnite and specular hematite
that envelopes quartz and massive stibnite veins. Additional soil sampling
undertaken in conjunction with trenching has now expanded the target to an
area of 2.0 by 0.4 kilometres. Drilling will aim to test mineralization
encountered in the trenches at depth. Soil sampling and a reconnaissance IP
geophysical survey has commenced to help expand the target, as well as refine
drill hole locations along trend.
    This program is being conducted under an exploration alliance agreement
with Northgate Minerals signed in December, 2005. The Boulevard Property is
held jointly by Rimfire and Northgate, with each company having funded the
initial $330,000 in targeting and exploration that led to staking of the
property. To date, Northgate has funded approximately $435,000 of the required
$1.5 million in exploration expenditures to earn an additional 10% interest
(for a total of 60%) in the property.
    This news release has been reviewed by Mark Baknes, M.Sc., P.Geo., VP
Exploration of Rimfire Minerals, a Qualified Person for the purpose of
National Instrument 43-101.