Colibri Resource Corporation has received assay results from 2152 m of diamond drill core on the Colibri Project, Sonora Mexico.  As described in more detail below (see also Tables 1-2 and maps posted on www.colibriresourcecorp.com), drilling intersected multiple anomalous intervals that returned gold assay values ranging from 25 ppb to 3.08 grams per metric tonne.  Total thickness of these anomalous intervals is 424 m.  Assays from selected anomalous zones indicate that conventional analyses of crushed samples (less than 150 sieve mesh) systematically underestimate the gold content of samples. Many samples greater than 150 mesh sieve yielded markedly higher gold assays than corresponding fine grained powders, an indication of coarse grained gold ("nuggets") similar to those visible in hand specimens from local mine dumps and underground mine workings.   

The Colibri Project is held by an option agreement to acquire 100% ownership of 6564 hectares made between the Mexican subsidiary of Colibri, Minera Halcones SA de CV, and a private Mexican company.   Exploratory drilling is mostly focused on down-dip and along-strike projections of historical underground mine workings and targets identified by an Induced Polarization geophysical survey.  Previous reverse-circulation drilling of these targets during 1994, 1998, and 2005 yielded significant gold mineralization (see News Release of January 25, 2006; see also Table 1 and drill hole location maps posted on www.colibriresourcecorp.com).  At San Francisco mine, the 1998 and 2005 drill holes intersected 19 intervals with greater than 500 ppb (0.5 g/t) gold.  These intercepts correspond to different structural levels of a NE-dipping quartz vein-reverse fault system.

Three areas were targeted for diamond drilling during the 2006-07 season: the San Francisco mine, the Naranja Zone and the Nopal Zone (see Table 1 and drill maps).  In this stage, Britton Brothers drilled mostly HQ diameter core with a few intervals of NQ diameter core.  Drilling conditions proved to be exceptionally difficult and water intensive, with broad intervals of strongly sheared, fractured rock encountered.  Core recovery was generally good, 90-100%.  Hematite-flooded breccia or gouge zones with quartz veins and stockworks are common features of recovered core in all holes.  Several holes were terminated due to difficult drilling conditions in strongly sheared, brecciated rock (CDH-1, 6, 7)

Every drill hole cut multiple intervals containing greater than 25 ppb gold. Table 2 reports assay results for each of these anomalous zones.  Initial assays of crushed samples (less than 100 mesh) yielded gold content greater than 500 ppb (0.5 g/t) for 11 samples, most corresponding to high grade targets intersected by previous RC drilling efforts.  However, grades of these core samples were lower than RC results in several cases. Because of the inability of core drilling to reproduce prior RC drill results, Colibri suspects a sampling and/or recovery problem in that the core assays do not report coarse gold or "nuggets".  Hand samples collected from underground mine workings and mine dumps contain coarse, visible gold associated with quartz and hematite. To test the extent of the coarse gold problem, Colibri analyzed a second split of samples from 104 anomalous intervals.  Additional columns in Table 2 compare gold analyses between the powdered (-150 mesh) and coarser (+150 mesh) fractions of these second samples.

Pertinent results of the diamond drill core analysis are:

1)      Each drill hole intersected broad intervals of disseminated gold mineralization in stockwork.  The total thickness of recovered core with greater than 25 ppb gold is 424 m (20% of the total 2152 meters drilled).

2)      Drilling intersected multiple higher grade (500 to 3080 ppb gold) intervals associated with shear zones and quartz breccias.  The total thickness of core returning gold assays greater than 500 ppb (0.5 g/t) is 19.1 m.

3)      Tests for coarse gold were conducted on 104 samples, 85 of which represent drill intervals with initial assays exceeding 25 ppb gold. Of these samples, 29 returned greater than 280 ppb (0.28 gpt) gold in the coarser than 150 mesh fraction, compared with lower concentrations below 150 mesh, a clear demonstration of coarse gold mineralization.  Most notable is sample CDH-499 where the greater than 150 mesh split of the sample contains 34.88 grams per tonne gold and the finer than 150 mesh split of the same sample 1.6 grams per tonne gold.  When combined the complete sample contains 3.08 gpt.

Other notes on specific target zones:

1)   Colibri is encouraged by results from the Naranja Zone, where drilling penetrated thenorthwest edge of a large geophysicalanomaly.  Holes CDH 6, 7, and 9 returned assays greater than 0.25 g/t gold from five intervals located at less than 90 m depth.  Hole CDH-7 was terminated at a depth of 91.1 meters due to difficult drilling conditions in fault gouge containing 0.12 gpt gold.   In this area, Induced Polarization surveying reveals a coupled resistivity and chargeability anomaly within a district of numerous dry placer mining operations and artesanal underground mines (see maps posted on www.colibriresourcecorp.com).  Also present in this area is a low-angle normal fault (detachment fault), manifested in nearby arroyos by broad zones of brecciation and hematite/caliche alteration.  This fault zone appears to form an undulating surface beneath the Naranja Zone, a geologic feature typical of the nearby operating mines and advanced prospects of this class.

2)   Results from the San Francisco mine area (drill holes CDH 1-5) confirm the presence of anomalous gold within a NE-dipping network of quartz veins and reverse faults.  Multiple intercepts returning assays greater than 0.5 g/t gold provide valuable infill data to integrate with results from 1998 and 2005.

3)   Drill holes NDH 1-4 from the Nopal Zone did not reproduce the broad intervals of high-grade gold reported from1994 RC drilling of holes NRC 8 and 9 (see Tables 1 and 2).   However, one 4.5 m interval of NDH-1 returned assays between 0.43 and 0.54 g/t gold for powdered samples, with one interval of 7.05 g/t for the greater than 150 mesh sample, compared with 0.54 gpt for the finer than 150 mesh sample.  Numerous sheared quartz veins throughout the Nopal zone have yielded high-grade rock chip samples (see Colibri Corporation prospectus posted on www.sedar.com).  This vein network is now mapped in detail (see www.colibriresourcecorp.com), and merits further sampling and drilling.

Colibri has not completed all tests of samples and is reviewing future sampling and drilling methods.  In comparing the four generations of drill data, inconsistent results from holes drilled into similar targets are interpreted to be a manifestation of the nugget effect coupled with intrinsic heterogeneity of gold mineralization that is a common characteristic of the operating nearby gold mines.  Other factors probably include significant contrasts between drilling techniques and assay labs, plus chronically poor sample recovery in intervals of sheared, mineralized rock.  Compilation and integration of results from the different stages of drilling is ongoing.

Core samples were split on site using a diamond saw.  Half of the sample was logged and stored on site and the other half bagged and delivered to Sonora Sample Preparatory Lab in Hermosillo, Mexico.  Sonora Sample Prep Lab initially prepared sample pulps consisting of the finer than 100 mesh fraction of crushed samples.  This split was sent to International Plasma Labs (IPL) in Vancouver.  In the second phase of core assays, Sonora Sample Prep sent the entire crushed sample to IPL.  IPL sieved the samples using 150 mesh screen, then weighed and assayed separately the greater than 150 mesh and less than 150 mesh fractions.  Assays were performed by IPL using a standard combination of atomic absorption and fire assay techniques.

Exploration was conducted under the supervision of J.J. Irwin, B.Sc., Ph.D., the qualified person under National Instrument 43-101 on this project.

Warrants Update

Colibri is happy to report that almost all the publicly traded half-share warrants have been exercised that were due to expire on July 28, 2007.  The additional funds received by the company now results in a cash position exceeding four million dollars to be spent on the drilling programs that will be initiated beginning October 2007 at our claim sites in Sonora, Mexico.

For further information

Visit our website at www.colibriresourcecorp.com or call Lance Geselbracht, P.E., (604) 669-7591

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