Diamonds and more diamonds

Striker Resources has returned what it believes are the best bulk sampling of diamonds results from a kimberlite pipe seen in Australia since the discovery of Argyle 25 years ago.

The sample comes from at its Seppelt 2 project in the North Kimberley.

Striker chairman Ewen Tyler said Seppelt 2 had produced 412 carats of commercial size diamonds from a 183 tonne bulk sample, the equivalent of 2.25 carats per tonne, which on face value is a world-class grade.

"The most important aspect at this stage is the number of large diamonds in the sample which is very positive pointer for the value of what we are seeing at Seppelt," he said.

Out of 412 carats from this 183 tonne sample we have four diamonds greater than two carats, 21 greater than one carat and many greater than half a carat.

The largest diamond to date weighed in just under three carats.

"If you draw a comparison with grades at other Australian diamond projects, Argyle was six carats per tonne but at the lower end of the quality scale, Merlin less than one carat averaging 0.25 per tonne or 25 carats per 100 tonnes (cpht) and Ellendale around 10cpht.

"Striker's earlier project at Ashmore averaged 7cpht.

"Whilst grade varies from mine to mine and pipe to pipe, the world standard is less than 100cpht or one carat per tonne."

"The quality of the diamonds looks good and we are assuming a value above $50 per carat at this stage.

DeBeers valued the Seppelt 1 diamonds that they recovered some years back at US$40 per carat," Mr Tyler said.

Ewen Tyler is the former chairman of the Argyle Diamond Mines Joint Venture and an Ashton director until 2000.

Striker's exploration manager responsible for Seppelt is Tom Reddicliffe, formerly Australian exploration manager of Ashton Mining who participated in the discovery of the Argyle and Ellendale pipes and implemented the exploration programs that resulted in the discovery of Merlin.

Mr Tyler said: "Diamond drilling has commenced to seek the size, shape and other details of the pipe and we suspect there may be extensions to the known pipe or parallelling structures that may add tonnage to the resource.

"Bulk sampling at Seppelt 2 has focussed on kimberlite just two to six metres below the surface.

"There is evidence that the prospectivity extends along a strike to the north in the direction of Seppelt 1, located approximately five kilometres away.

Seppelt 1 is running at 43 carats per 100 tonnes with 1.7 million tonnes of inferred kimberlite defined."

Striker recently reported gem quality diamonds of 1.95, 1.55 and 1.2 carats in size from Seppelt 1 and last week announced the recovery of a 3.15-carat diamond, the largest from a Seppelt pipe so far.