Jwaneng
Diamond – C3
21.7 km2
Active
1 licence
Eastport holds one exploration licence in the Jwaneng area that covers 21.7 km2. The licence is located 20 km’s north-east of Debswana’s Jwaneng Mine, acknowledged as “the richest diamond mine in the world by value”, producing over 11 million carats per annum.
At present, three kimberlite pipes are known within Eastport’s Jwaneng diamond licence, with the geological relationships implying a long history of kimberlite emplacement in the area. The diamond content of the three kimberlite pipes is largely unknown and each appears to have been historically under-sampled.
The Kgare pipe is the most well understood of the kimberlites at Jwaneng, being diamondiferous, and having returned encouraging mineral geochemistry that is comparable to indicators found in Debswana’s Jwaneng mine.
Chromite & Garnet Chemistry
At Kgare, kimberlite indicators, a suite of characteristic mineral grains commonly entrained in kimberlite, are highly encouraging. Two in particular are meaningful in the exploration for kimberlite, namely chromites and garnets, which are used to verify that the kimberlite magma has traversed the diamond stability field, a discrete layer within the earth’s mantle, on its way to the earth’s surface. Today, the science of kimberlite discovery has advanced to the point where well defined “fields” are used to segregate the “positive” indicators. The charts below demonstrate how both the chromite and garnet indicators are suggestive of significant opportunity for diamond discovery.
The chromite chemistry follows both the mantle and kimberlite trends, concluding with a significant number of data points within the diamond inclusion fields, which implies that the diamond potential is high.
The equally promising garnet chemistry, G10 types to the left of the Gurney line, records a notable number of grains above the “diamond-graphite constraint” (GDF) of Grutter (2004). This informs that Kgare has traversed the diamond stability field and that the kimberlite may contain diamonds.
The chromite chemistry follows both the mantle & kimberlite trends ending with a significant number of data points within the diamond inclusion fields. This tells us that the diamond potential is high.
The equally promising garnet chemistry, G10 types to the left of the Gurney line, records a startling number of grains above the “diamond-graphite constraint” (GDC) of Grütter (2004). This tells us that Kgare has traversed the diamond stability field and that the kimberlite may contain diamonds.
Work Programme
Following approval of the licence extension, Eastport will conduct a survey of three infill lines of HLEM over the EVB003 kimberlite target. The objective of this survey is to better define the target boundaries and assess its size potential. The EVB003 target is located approximately 300 metres southeast of the Kgare kimberlite pipe, making its proximity very attractive.
EVB003 will then be tested using a single dipping core drill hole. Core will allow for characterisation of the kimberlite and facies mapping. Between 500-1000kg of kimberlite will be collected for diamond and mineral indicator recovery. Indicator chemistry will be determined to assist with the economic potential of the kimberlite.