GRAPHITE PROJECT

Delineation and development of the Oakdale graphite project is a downstream core focus of Oakdale Resources Limited.

 

Oakdale Project Graphite Distribution

The Company’s tenements, on the Eyre Peninsula of South Australia, has the potential to contain extensive graphitic units.  The first potential project drilled at Oakdale, has graphite rich saprolitic clay units that have been delineated and are 500 metres wide, extend for over 1.5 kilometres and are approximately 20 metres thick.

The recent drill program at Oakdale Project commenced in March 2015 and was completed in September 2015 with the completion of 288 aircore drill holes for 16,643.5 metres. A further 42 holes for 2480.5 metres have been drilled at Oakdale East where the graphite units are open to the east and the west.

The extensive drilling program at Oakdale and to a lesser extent at Oakdale East outlined a substantial JORC compatible resource of 6.32 Mt of 4.7% TGC.  Additional Mineral Resource potential occurs at Oakdale East and Oakdale North.

 

The oxidised soft graphitic clays within the delineated Ore Resource can be cheaply and readily mined within a shallow open pit without drilling and blasting.  The soft graphitic clays will also be recovered at a very low treatment cost because they will not require crushing or primary grinding.

 

Ongoing metallurgical test work by Bureau Veritas in Adelaide and ALS Laboratories in Burnie has demonstrated:

  • At least 60% of the ore can be rejected at 90% passing ≈1, 200µm for less than a 14% TGC loss, this involves both pre concentrations using gravity separation & desliming at about 15µm.

  • Most of the TGC losses are in the <15µm fraction, which is a low value product.

  • The ore does not require crushing & primary grinding, but does require secondary grinding and/or attritioning.

  • Some Oakdale ores yield very high TGC recoveries of over 95% to a >60% TGC concentrate using just whole of ore flotation.

  • However, nontronite & other clay minerals interfere with flotation for other ore types:-

 

    • For these ores, desliming removes the nontronite & improves TGC recovery from about 10% to >80%.

    • Concentrate grade also improves from ≈ 8%TGC to > 86% TGC.

  • The graphite flakes are very thin:-

    • Being only between 3µm to 6µm thick on average & are fragile. 

    • The indicative average grain size or D50 of the graphite seems to vary considerably from ≈75µm for one or two ores to ≈180µm for ten other ores.

  • Very little >425µm free, clean graphite was found in any ore type.

  • Clay sandwiching between graphite flakes or adhering to the graphite flake surface limits the flotation concentrate grade to ≈80% to 85% TGC at the very best, this is without grinding, washing or attritioning.

  • The current sizing estimate of the final Oakdale processing concentrate assaying >90% TGC is given below.

  • It is aimed to produce a concentrate assaying > 98% TGC from the dressing plant.