Rimfire Minerals Corporation: Copper-Gold Mineralization Intersected in Wernecke Breccia JV Drilling

Jason Weber, President and CEO of Rimfire Minerals Corporation (TSX VENTURE:RFM)
reports that results from drilling at the Hoover Property have been received
from the Wernecke Breccias Project, a joint venture with Fronteer Development
Group Inc. Exploration conducted throughout the 2007 field season targeted iron
oxide copper-gold-uranium targets and stand-alone uranium targets on the Joint
Venture's 373-sq-km land package in the Wernecke Mountains of Canada's
north-central Yukon Territory.


The latest holes continue to expand the limits of known copper-gold
mineralization at the Hoover Property. New drilling highlights include:


- 1.84% copper and 0.53 grams per tonne gold over 17.3 metres in HV07-27.

- 0.56% copper and 0.16 grams per tonne gold over 45.5 metres in HV07-27.

- 1.20% copper and 0.48 grams per tonne gold over 7.9 metres in HV07-26.

Mineralization at the Hoover Property has been intersected in 11 widely spaced
holes and approximately 500 m of strike length. This mineralization remains open
for expansion to the north and south as well as at depth. Anomalous
copper-in-soil geochemistry has been detected as far as 800 m to the south along
strike from the most southerly drill hole.


Final drill results from the Hoover Property are summarized below:



-------------------------------------------------------------------------
2007 Hoover drill results
Interval   Hole No.   From (m)   To (m)   Interval (m)   Au (ppm)   Cu (%)
             HV07-26    276.7    327.2           50.5       0.07     0.24
Including    HV07-26    319.3    327.2            7.9       0.48     1.20
-------------------------------------------------------------------------
             HV07-27     19.5     65.0           45.5       0.16     0.56
including    HV07-27     23.6     26.4            2.8       0.30     1.17
Including    HV07-27     51.0     59.0            8.0       0.27     1.21
             HV07-27    204.7    222.0           17.3       0.53     1.84
-------------------------------------------------------------------------
Previously announced 2007 results
             HV07-19    214.8    238.0           23.2       0.21     0.39
             HV07-19    264.6    313.0           48.4       0.12     0.28
-------------------------------------------------------------------------
             HV07-20      NSA
-------------------------------------------------------------------------
             HV07-21    119.0    135.4           16.4       0.22     0.86
             HV07-21    191.0    214.2           23.2       0.05     0.41
             HV07-21    273.4    350.0           76.6       0.11     0.23
-------------------------------------------------------------------------
             HV07-22     79.7    168.2           88.5       0.11     0.55
-------------------------------------------------------------------------
             HV07-23      NSA
-------------------------------------------------------------------------
             HV07-24      NSA
-------------------------------------------------------------------------
             HV07-25    170.0    254.0           84.0       0.08     0.12
             HV07-25    347.0    365.0           18.0       0.12     0.15
-------------------------------------------------------------------------
Note: The true width of the mineralized zones is estimated to be
      approximately 75% of those stated. HV07-26 was lost in
      mineralization. HV07-23 and 24 - holes were lost prior to reaching
      target depth.



A comprehensive table listing Hoover drill results, including historical
drilling, and a plan map showing drillhole distribution and soil geochemistry
can be found at http://www.rimfire.bc.ca/s/Wernecke_Breccias.asp.


The 2007 Wernecke Breccias exploration program was operated by Fronteer, and
funded pro-rata by Fronteer (80%) and Rimfire (20%). Remaining results from the
2007 program will be released once the data is compiled.


Assay results have been prepared under the guidance of David Kuran, P. Geo, who
is designated as a Qualified Person with the ability and authority to verify the
authenticity of and validity of this data. All samples were analyzed by ALS
Chemex, North Vancouver, BC, using ICP-AES and fire assay. Assays were completed
with uranium determinations by ME-MS-61 ICP geochemical analysis with samples
returning over 1000 ppm U were then analyzed by U-XRF-10 analysis.


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,
Arcus Development Group Inc. and BWG.


On behalf of Rimfire Minerals Corporation

Jason Weber, P.Geo., President & CEO