Ellendale 9 Alluvials Prospect
Key Points
- Extensive historic alluvial mine-workings and prospects north of the Ellendale 9 open pit
- Mining at the E9 West alluvial Channel was suspended when KDC went into administration on 1 July 2015, leaving broad areas of high sampled grades up to 41.6 carats per hundred cubic metres (cphm3) still unmined
- Historic mined grades are high, from 2005-08, Blina Diamonds NL treated 109,386 cubic metres of gravel at the very attractive average grade of 24.2 carats per hundred cubic metres (cphm3) at the E9 west channel
- Mining Lease M04/477 has been granted over the Ellendale 9 alluvials
- GIB are moving to obtain all necessary permitting to commence sampling and trial mining as swiftly as possible
GIB Executive Chairman Jim Richards at the E9 West alluvial mine. This panel was mined by KDC just prior to suspension of mining and administrators being appointed (July 2015). Excellent grades up to 41.4cphm3 surround this panel in broad areas of unmined alluvials (Figure 3)
Figure 1: Gibb River Diamond Project Tenure & Location Map
1.0 Ellendale 9 Alluvials Target
Extensive areas of alluvials have been previously defined to the north of the E9 open pit. Some of these E9 North Alluvials have been mined and have demonstrated excellent grades, which includes production of the E9 signature Fancy Yellow diamonds.
Table 1: Historic Mining and Exploration at the E9 Alluvials
Diamonds recovered in the -14 to +1.5mm size fraction for West and -14 to +1.2mm size fraction for East
Figures 2, 3 and 4 illustrate the areas mined and the target areas which are still unmined. Sample pit grades in unmined areas are shown, although these areas are mostly unsampled and require follow up pitting. The solid green line is the alluvial target zone determined by Nb/Y geochemistry (<0.95) from termite mound sampling, which proved to be a highly effective method in tracking alluvials derived from E4 and E9. GIB is using this data and historic pit sampling/mining to re-interpret the prospective alluvial channels for future bulk sampling/trial mining operations.
GIB believe these areas are very underdone in terms of exploration pitting where large areas of extremely prospective channel targets have not been trenched or sampled (Figures 2, 3 and 4). Even more obvious targets are the shallow gravels and high grades in previous pits were not mined or followed up.
These areas are wide open for the use of the latest in ground penetrating radar (GPR) to define new channel targets and the most prospective trap site areas within existing channels. This new technology has the potential to break open this area for new interpretations and discoveries, as it did for the Blina Alluvials2.
Mining at the E9 West alluvial Channel was suspended when KDC went into administration on 1 July 2015, leaving areas of high sampled grades up to 41.6 cphm3 still unmined (Figure 3).
GIB is excited by the potential of these areas, especially as the E9 East alluvials are open in all directions of the previous mining and the E9 West alluvials are open to the north and east. The largest stone recovered from the E9 East Alluvials was a 9.06 carat yellow gem (Boxer 2018).
E9 Alluvials West and East Channels
Mr Richards standing on the area cleared and permitted for mining by KDC on the E9 West Alluvials. This area was not mined and is a stand-up target for GIB
E9 West Alluvials. Excellent gravels at the edge of the mined block on the E9 West Alluvials
View from the northern edge of the E9 N-East 1
mining block, looking south along the channel bed (photo by GMI Rockett)
Diamonds recovered from the E9 East alluvials 2008 mining campaign. Note the high proportion of larger stones and Fancy Yellows. Largest stone is 9.06 carats (photo by JB Ward).
Figure 2: E9 Alluvials West and East Channel Targets
Figure 3: E9 Alluvials West Channel Targets
Figure 4: E9 Alluvials East Channel Targets
2.0 Summary
There are numerous exciting opportunities available for near term processing of the E9 alluvials. Historic mined grades are high, from 2005-08, Blina Diamonds NL treated 109,386 cubic metres of gravel at the very attractive grade of 24.2 carats per hundred cubic metres at the E9 west channel. A Mining lease has been applied for over the area and GIB are moving to expedite the grant of all permits to expedite bulk sampling and trial mining.
References:
1Further detailed information including the Table 1 (JORC Code, 2012 Edition) and references are available on the GIB ASX Release dated 9 October 2015, click here
2Blina Diamond Project, Gamechanger GPR Survey; GIB ASX Release dated 18 October 2017, click here
3Trenching Discovers New Gravel Targets at Blina; GIB ASX Release dated 6 August 2018, click here
4POZ to Bid for the Ellendale Diamond Mine; GIB ASX Release dated 4 September 2018, click here
GIB Secures Ellendale Diamond Mine Leases; GIB ASX Release dated 23 December 2019, click here
Bulletin 132 (Geological Survey of Western Australia); The kimberlites and lamproites of Western Australia by A.L. Jaques, J.D. Lewis and C.B. Smith.
The information in this report that relates to current and previously reported exploration results and the JORC Exploration Target is based on information compiled by Mr. Jim Richards who is a Member of The Australasian Institute of Mining and Metallurgy and a Member of the Australian Institute of Geoscientists. Mr. Richards is a Director of GIB River Diamonds Limited. Mr. Richards has sufficient experience which is relevant to the style of mineralisation and type of deposit under consideration and to the activity which he is undertaking to qualify as Competent Person as defined in the 2012 Edition of the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves. Mr. Richards consents to the inclusion in the report of the matters based on the information in the form and context in which it appears.
