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Snowfield Development Corp. ("Snowfield" or the "Company") is pleased to announce that it has received the results from till samples sent for recovery of kimberlitic indicator minerals from an area northeast of the Mud Lake diamondiferous kimberlite. Electron microprobe analysis has been completed on 850 indicator minerals derived from till sampling in an area northeast and in an up-ice direction from Mud Lake. The Mud Lake kimberlite, progressing through a 500 tonne bulk-sample testing for diamond recovery and this new prospective area are part of Snowfield's Ticho Diamond Project, located approximately 50 kilometres southeast of Yellowknife, N. W. T., Canada.
Overburden Drilling Management of Nepean, Ontario recovered the till sample indicator minerals. R. L. Barnett Consulting Inc. of London, Ontario undertook electron microprobe analyses of polished mineral grains. Roberta Flemming, Dept. of Earth Sciences, University of Western Ontario, London, Ontario undertook crystal structure analyses of green garnets recovered from the samples. The electron microprobe and crystal structure analyses work reported herein establish a potential for the kimberlite source of the indicator minerals to be diamondiferous.
The latest results add to the data of previously reported analyses of indicator mineral grains collected in a systematic surface sampling program over an area approximately 2000 metres by 1000 metres northeast and up ice from Mud Lake. In this sampling area there are several sample sites with elevated counts of kimberlitic indicator minerals and a high percentage of pyrope garnets noted for having kelyphitic rims suggesting a proximal source. (A Kelyphitic rim is a thin outer coating around a pyrope garnet that does not survive lengthy transportation, due to glaciation, from the source kimberlite).
Electron microprobe analysis of indicator minerals from surface sampling in the area of interest northeast of Mud Lake reveals distinct trends in chemical compositions that may be of importance for exploration purposes. These trends include three key regions of compositions that include pyrope garnets, classified as G9, that extend the Lherzolite trend due to their elevated chromium oxide compositions. Outside the Lherzolite trend are two other regions; one region contains green garnet grains that fall in the miscibility gap between ugranditic and pyralspitic garnets; the second region contains high counts of another group of garnets that fall between the Lherzolite trend and the green garnets in the miscibility gap. Various grains from these three trends are used for target selection for drilling. Several key areas inside the overall surface sampling area are of high interest with elevated counts of these key indicator minerals.
In addition to electron microprobe analysis a number of green garnets were sent for crystal structure analysis. Green garnets that fall into the miscibility gap can be identified by chemical composition and crystal structure. The green garnet grains were submitted for crystal structure analysis to determine their unit cell lengths and returned dimensions that plot in the miscibility gap between known cell dimensions of garnets between ugranditic and pyralspitic garnets. These green garnets are rare and Snowfield believes these to be important diamond indicator minerals; public literature reveals that in every location where these garnets have been found the associated kimberlites have proved to be diamondiferous, including the Mud Lake kimberlite. Two of the most important documented diamondiferous kimberlites mined containing green garnets are the Premier mine in South Africa and the Udachnaya mine in Russia.
The Mud Lake kimberlite is the first publicly reported bedrock source in the Slave Province where green garnet diamond indicator minerals have been found. The green garnets identified from samples taken at a significant distance up ice from Mud Lake suggest a new diamondiferous kimberlite target area northeast of the Mud Lake kimberlite.
During 2007 drilling has been underway testing several geophysical targets. Future drilling will also focus on areas where highly prospective indicator minerals have been found. Additional surface sampling was done in the past few months, to further refine the indicator mineral trains, and these samples have been submitted for indicator mineral recovery and probing.
Marvin A. Mitchell, P. Eng., a Qualified Person per NP 43-101, has reviewed and approved the content of this news release.
Please see the glossary at the end of this news release for an explanation of terms.
ON BEHALF OF THE BOARD
"Marvin A. Mitchell"
Director
SNOWFIELD DEVELOPMENT CORP.
Glossary:
Pyralspite garnets are a group of garnets that include pyrope, almandine and spessartine garnets.
Ugrandite garnets are a group of garnets that include uvarovite, grossular and andradite garnets.
The miscibility gap is a range of chemical compositions that falls between pryralspite garnets that are generally low in calcium oxide and ugrandite garnets that are generally high in calcium oxide not commonly found in crustal conditions.
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