Caldera Resources Inc.-Runton Igneous Complex-Southern Dyke

Market Wire, January, 2007

Caldera Resources Inc. (TSX: CDR) is pleased to announce preliminary results from the trenching program, which was carried out in conjunction with a drill program during November 2006, by Peak Drilling Services.

Seven reverse-circulation holes were drilled on the Southern Dyke for a total of 374 metres and two trenches were excavated at the same location as the drill holes. The programs were restricted in time due to the extreme daily temperatures of 55 degrees C.

During the 2005 drill program at Runton, one drill hole on the Southern Dyke intersected a very weathered ultra basic rock, but due to limited sample, the scope of assessment was not sufficient to determine any meaningful conclusions.

Detailed geophysical modeling using close-spaced aeromagnetic data indicates that this anomaly is approximately 60 metres in width and plunges steeply to the south. The aeromagnetic anomaly is a minimum of 10 km long and where drilled and excavated was only 1.5 metres below the surface. The dyke's depth below surface is thought to increase only slightly along its strike to the west-northwest.

Results From 2006 Program

A series of vertical reconnaissance drill holes and shallow trench excavations during the November 2006 program has penetrated the Southern Dyke, which is interpreted to be dipping steeply to the south at this locality. Examination of rock fragments taken from drill cuttings of the dyke indicates that it is an ultramafic saprolite. Shallow excavations across part of the dyke encountered greenish yellow clay material (yellow ground) which appears to have protruded into the surrounding volcanoclastics due to the considerable volume expansion caused the serpentinisation of olivine and the subsequent formation of clays in the body itself.

Approximately 250 kilograms of material has been taken from the shallow excavations for examination. Two relatively small sub-samples of 10 kilograms each was submitted to Diatech Heavy Mineral Services and Diamond Recovery Services, both of Perth, Western Australia, in order to rapidly assess this new find for diamond indicator potential.

Diamond indicator minerals such as chromian spinel (chromite), pyrope garnet, picroilmenite and clinopyroxene were recovered from the sample. These minerals were then quantitatively analysed using a fully calibrated SEM at CSIRO and electron microprobe at UWA.

Many chromian spinel (chromite) compositions plot within the generalized field for diamond intergrowths and inclusions; Cr2O3 contents for these grains range from 63.8 to 67.6 wt% and MgO contents range from 9.2 to 10.5 wt%.

Numerous peridotitic G9 pyrope garnet and some peridotitic G10 pyrope garnets were recovered from the 10 kilogram sample of yellow ground. In addition, a number of eclogitic G10 pyrope garnets were also recovered from the sample. The Na contents of the eclogitic G10 garnets are typical of those garnets found associated with diamonds.

One picroilmenite grain was recovered which has a Cr2O3 content of 0.53 wt%, 13.14 wt% MgO and has an unusually high NiO content of 0.48 wt% and low Fe203/FeO ratio. Several rutile grains were also recovered that contain up to 0.13 wt% Cr2O3 and 0.27 wt% Nb2O5. A clinopyroxene was also recovered in this extremely altered material with an Mg/(Mg Fe) equals 92.2 containing 0.82 wt% Cr2O3, 1.15 wt% TiO2 and 0.4 wt% Na2O.

This extraordinary occurrence of the complete array of the important diamond indicator minerals such as pyrope garnet, chromian spinel (chromite), picroilmenite and clinopyroxene from a very small, extremely weathered and altered sample taken from a shallow excavation on the Southern Dyke is highly significant. This information coupled with the detailed aeromagnetic data defining this dyke indicates that this is a potentially very large diamond indicator bearing ultramafic body with a footprint of at least 50 ha.

The presence of G10 and G9 pyrope garnets as well chromian spinels (chromites) that have compositions similar to those included in diamonds and associated with diamond intergrowths indicate that the potential to discover diamonds in the sample is extremely high. Furthermore, the low Fe3 /Fe2 ratio in the picroilmenite and low TiO2 of the chromian spinel (chromite) grains implies that the oxygen fugacity was low during the bodies entrainment and any metasomatic events prior to or post its rapid ascent to surface were minimal, indicating that any diamonds present in this ultramafic body are likely to be well preserved.

Without more mineral chemistry and fresh bulk rock chemical information the precise nature of the ultramafic body cannot be immediately determined, however based on the limited information available to date, this body is likely to be a kimberlite.

Examination of the reworked volcanoclastic sediments that have been recovered from reconnaissance drilling adjacent to Southern Dyke has produced an abundance of chromian spinel (chromite) grains whose compositions indicate that they are 'diamond associated'. It would appear that these volcanoclastic chromian spinels (chromites) are very similar to those obtained from the shallow excavation on the Southern Dyke itself. In the absence of more specific information, it seems likely that these two entities are related, indicating that the sheet of reworked volcanoclastic sediments immediately adjacent to Southern Dyke was originally sourced from the ejected material that was produced by the phreatomagmatic volcanic activity of the Southern Dyke. It seems likely that the Southern Dyke represents the remnants of a fissure that fed a number of kimberlitic volcanoes that straddled a line, which is now crudely represented by the aeromagnetic anomaly of the Southern Dyke.