Rimfire Minerals Corporation: Williams Project Update

Jason Weber, President and CEO of Rimfire Minerals Corporation (TSX VENTURE:RFM)
reports final results from the 2007 exploration of the Williams Property,
located 150 kilometres southeast of Dease Lake, BC. This work, funded by Arcus
Development Group Inc., consisted of mapping, prospecting and rock, silt and
soil geochemical sampling to evaluate new claims staked in 2006. Ground work was
also undertaken at the T-Bill high-grade gold target to refine targets for
drilling, and at the GIC porphyry copper-gold prospect. Soil geochemical
sampling led to the identification of the LN anomaly, a large molybdenum,
copper+/-gold-in-soil geochemical anomaly immediately east of the GIC prospect. 


Arcus has informed Rimfire that it does not intend to continue exploration of
the Williams Property. Rimfire will retain 100% of the property, which includes
two drill-ready targets at the T-Bill and GIC prospects. In keeping with
Rimfire's business model, management will be seeking a partner to advance both
prospects.


T-Bill Prospect

The focus of the 2007 program at the T-Bill was to confirm the orientation of
quartz-carbonate-arsenopyrite veins in order to refine targets for subsequent
drilling. This program included hand trenching in select areas to expose veining
that previous workers had intersected in drilling. Eighteen historic holes have
been drilled within a 900 by 500 metre area to date resulting in 11 separate 2.0
metre intersections in excess of 12.0 g/t gold, including 35.0 g/t gold and 24.8
g/t over 2.0 metres. Potential for large low-grade gold style targets is
evidenced by intersections from the same area that include 1.1 g/t gold over 75
metres (true width). Hand trenching of the T-Bill veining confirmed management's
interpretation that the vein swarm is steeply dipping with a northwest/southeast
strike.


GIC Prospect

Previous programs at the GIC Prospect include drilling in 2006 that identified
porphyry style alteration and pyrite dominant mineralization coincident with an
Induced Polarization (IP) chargeability high anomaly. The 2007 program focussed
on unexplored jarosite gossans east of the area drilled in 2006, and led to the
identification of the LN Anomaly, a 450 by 900 metre molybdenum,
copper+/-gold-in-soil anomaly (Mo greater than 16 ppm, Cu greater than 129 ppm).
The anomaly, which remains open to the east, is coincident with an airborne
magnetic high. 


"We were successful in verifying the orientation of veining at the T-Bill
Prospect and determining that the porphyry-style hydrothermal system at the GIC
extends outside of the area investigated by drilling in 2006. We now have
excellent drill targets at both prospects," stated Mark Baknes, VP Exploration
for Rimfire. "Molybdenum-copper soil geochemistry may be vectoring us from
pyrite (iron) dominated mineralization to copper, gold and molybdenum-rich
mineralization east of the GIC. At the T-Bill, we now have much more certainty
in the orientation of high-grade gold veining which will allow us to
systematically test these veins by drilling. We will be seeking a partner to
test these two targets."


The 2007 work program was conducted under the direction of Henry Awmack, P.Eng.,
of Equity Engineering Ltd., a Qualified Person for the purpose of National
Instrument 43-101. Assays were completed by ALS Chemex Labs of North Vancouver,
BC.


About Rimfire

Rimfire Minerals Corporation is an aggressive, well-financed mineral exploration
company with a portfolio of highly prospective gold and silver properties in
western North America. Current and former partners include AngloGold Ashanti
Limited, Barrick Gold Corporation, Newmont Mining Company, Northgate Minerals
Corporation, Fronteer Development Group, Rubicon Minerals Corporation, Cangold
Limited, American Creek Resources Ltd., Island Arc Exploration Corporation and
BWG.


On behalf of Rimfire Minerals Corporation

Jason Weber, P.Geo., President & CEO