Sheffield extends high-grade at Thunderbird

THE DRILL SERGEANT: Sheffield Resources (ASX: SFX) has received further high-grade drilling results from the company’s 100 per cent-owned Thunderbird mineral sands project, located near Derby in Western Australia.

The results are from extensional drill holes drilled during the company’s 2014 aircore drilling program and include:

Up-dip Extension

THAC484
36 metres at 10.3 per cent heavy minerals (HM) from 7.5m, including 27m at 12.6 per cent HM from 10.5m;

THAC487
42m at 8.63 per cent HM from 6m, including 27m at 11.9 per cent HM from 13.5m;

THAC486
42m at 8.46 per cent HM from 12m, including 24m at 12.0 per cent HM from 22.5m; and

THAC488
39m at 8.57 per cent HM from 10.5m, including 16.5m at 13.8 per cent HM from 22.5m.

Down-dip Infill & Extension

THAC505
60m at 8.1 per cent HM from 70.5m, including 27m at 11.4 per cent HM from 81m;

THAC504
75m at 6.14 per cent HM from 64.5m, including 27m at 9.5 per cent HM from 78m;

THAC511
43.5m at 9.69 per cent HM from 76.5m

(>3 per cent HM cut-off, including >7.5 per cent HM cut-off).

 

Plan view of Thunderbird deposit 32-year pit shell outline on Mineral
Resource Classifications showing location of drillholes. Source: Company
announcement

Sheffield said the latest results, together with previously-released high-grade intersections, demonstrate thick, high-grade mineralisation extends beyond the project’s current resource limits in the up-dip direction.

The company said the results of down-dip drilling also demonstrated continuity of mineralisation within the part of the resource currently classified as Inferred, extending the mineralisation beyond the current resource boundaries.

All results are also outside the 32-year life-of-mine (LOM) optimised pit shell used in the April 2014 Scoping Study, which the company considers to highlight potential to improve the project’s economics.

“These are another excellent set of drill results from Thunderbird,” Sheffield Resources managing director Bruce McQuitty said in the company’s announcement to the Australian Securities Exchange.

“The discovery of additional high-grade mineralisation in the up-dip region is particularly significant because our Scoping Study delivered higher margins in early production years by incorporating similar high-grade mineralisation in adjacent areas.

“This latest discovery is just one of several value enhancement opportunities we are investigating during the pre-feasibility stage.

“We look forward to delivering the next milestones which are the resource update and Pre-feasibility Study results.”

The Thunderbird project currently has total mineral resources of 2.62 billion tonnes at 6.5 per cent HM (Measured, Indicated and Inferred) for 170 million tonnes of contained HM, including a high-grade component of 740 million tonnes at 12.1 per cent HM.

The Thunderbird Scoping Study, released in April, showed the project has potential to generate consistent cash margins from high levels of production over an initial
32-year mine life.

All drilling and field-based pre-feasibility activities are now complete for 2014.

Results from infill aircore drilling at Thunderbird and regional exploration drilling are expected to be received during Q4 2014 and Q1 2015, respectively.

Pre-feasibility work is well advanced and is on schedule to be finalised during
Q1 2015.

Website: www.sheffieldresources.com.au